noble (5) ovn-nb.5.gz

Provided by: ovn-common_24.03.2-0ubuntu0.24.04.1_amd64 bug

NAME

       ovn-nb - OVN_Northbound database schema

       This  database  is  the  interface  between OVN and the cloud management system (CMS), such as OpenStack,
       running above it. The CMS produces almost all of the contents of the  database.  The  ovn-northd  program
       monitors the database contents, transforms it, and stores it into the OVN_Southbound database.

       We generally speak of ``the’’ CMS, but one can imagine scenarios in which multiple CMSes manage different
       parts of an OVN deployment.

   External IDs
       Each of the tables in this database contains a special column, named external_ids. This  column  has  the
       same form and purpose each place it appears.

              external_ids: map of string-string pairs
                     Key-value  pairs  for  use  by  the  CMS.  The CMS might use certain pairs, for example, to
                     identify entities in its own configuration that correspond to those in this database.

TABLE SUMMARY

       The following list summarizes the purpose of each of the tables in  the  OVN_Northbound  database.   Each
       table is described in more detail on a later page.

       Table     Purpose
       NB_Global Northbound configuration
       Copp      Control plane protection
       Logical_Switch
                 L2 logical switch
       Logical_Switch_Port
                 L2 logical switch port
       Forwarding_Group
                 forwarding group
       Address_Set
                 Address Sets
       Port_Group
                 Port Groups
       Load_Balancer
                 load balancer
       Load_Balancer_Group
                 load balancer group
       Load_Balancer_Health_Check
                 load balancer
       ACL       Access Control List (ACL) rule
       Logical_Router
                 L3 logical router
       QoS       QoS rule
       Mirror    Mirror Entry
       Meter     Meter entry
       Meter_Band
                 Band for meter entries
       Logical_Router_Port
                 L3 logical router port
       Logical_Router_Static_Route
                 Logical router static routes
       Logical_Router_Policy
                 Logical router policies
       NAT       NAT rules
       DHCP_Options
                 DHCP options
       Connection
                 OVSDB client connections.
       DNS       Native DNS resolution
       SSL       SSL configuration.
       Gateway_Chassis
                 Gateway_Chassis configuration.
       HA_Chassis_Group
                 HA_Chassis_Group configuration.
       HA_Chassis
                 HA_Chassis configuration.
       BFD       BFD configuration.
       Static_MAC_Binding
                 Static_MAC_Binding configuration.
       Chassis_Template_Var
                 Chassis_Template_Var configuration.

NB_Global TABLE

       Northbound configuration for an OVN system. This table must have exactly one row.

   Summary:
       Identity:
         name                        string
       Status:
         nb_cfg                      integer
         nb_cfg_timestamp            integer
         sb_cfg                      integer
         sb_cfg_timestamp            integer
         hv_cfg                      integer
         hv_cfg_timestamp            integer
       Common Columns:
         external_ids                map of string-string pairs
       Common options:
         options                     map of string-string pairs
         Options for configuring OVS BFD:
            options : bfd-min-rx     optional string
            options : bfd-decay-min-rx
                                     optional string
            options : bfd-min-tx     optional string
            options : bfd-mult       optional string
         options : ignore_chassis_features
                                     optional string
         options : mac_prefix        optional string
         options : mac_binding_removal_limit
                                     optional string, containing an integer, in range 0 to 4,294,967,295
         options : fdb_removal_limit
                                     optional string, containing an integer, in range 0 to 4,294,967,295
         options : controller_event  optional string, either true or false
         options : northd_probe_interval
                                     optional string
         options : ic_probe_interval
                                     optional string
         options : nbctl_probe_interval
                                     optional string
         options : northd_trim_timeout
                                     optional string
         options : use_logical_dp_groups
                                     optional string
         options : use_parallel_build
                                     optional string
         options : ignore_lsp_down   optional string
         options : use_ct_inv_match  optional string
         options : default_acl_drop  optional string
         options : debug_drop_domain_id
                                     optional string
         options : debug_drop_collector_set
                                     optional string
         options : use_common_zone   optional string, either true or false
         options : northd-backoff-interval-ms
                                     optional string
         Options for configuring interconnection route advertisement:
            options : ic-route-adv   optional string
            options : ic-route-learn optional string
            options : ic-route-adv-default
                                     optional string
            options : ic-route-learn-default
                                     optional string
            options : ic-route-blacklist
                                     optional string
       Connection Options:
         connections                 set of Connections
         ssl                         optional SSL
       Security Configurations:
         ipsec                       boolean
       Read-only Options:
         options : max_tunid         optional string

   Details:
     Identity:

       name: string
              The name of the OVN cluster, which uniquely identifies the OVN cluster throughout all OVN clusters
              supposed to interconnect with each other.

     Status:

       These columns allow a client to track the overall configuration state of the system.

       nb_cfg: integer
              Sequence number for client to increment. When  a  client  modifies  any  part  of  the  northbound
              database  configuration  and  wishes to wait for ovn-northd and possibly all of the hypervisors to
              finish applying the changes, it may increment this sequence number.

       nb_cfg_timestamp: integer
              The timestamp, in milliseconds since the epoch, when ovn-northd sees the latest nb_cfg and  starts
              processing.

              To print the timestamp as a human-readable date:

                        date -d "@$(ovn-nbctl get NB_Global . nb_cfg_timestamp | sed ’s/...$//’)"

       sb_cfg: integer
              Sequence  number  that  ovn-northd  sets  to  the  value  of nb_cfg after it finishes applying the
              corresponding configuration changes to the OVN_Southbound database.

       sb_cfg_timestamp: integer
              The  timestamp,  in  milliseconds  since  the  epoch,  when  ovn-northd  finishes   applying   the
              corresponding configuration changes to the OVN_Southbound database successfully.

       hv_cfg: integer
              Sequence  number  that  ovn-northd  sets to the smallest sequence number of all the chassis in the
              system, as reported in the Chassis_Private table in the southbound database. Thus,  hv_cfg  equals
              nb_cfg  if all chassis are caught up with the northbound configuration (which may never happen, if
              any chassis is down). This value can regress, if a chassis was removed from the system and rejoins
              before catching up.

              If  there  are  no  chassis,  then  ovn-northd  copies  nb_cfg  to hv_cfg. Thus, in this case, the
              (nonexistent) hypervisors are always considered to be caught up. This means that  hypervisors  can
              be  "caught  up"  even  in  cases  where sb_cfg would show that the southbound database is not. To
              detect when both the hypervisors and the southbound database are caught up, a client  should  take
              the smaller of sb_cfg and hv_cfg.

       hv_cfg_timestamp: integer
              The largest timestamp, in milliseconds since the epoch, of the smallest sequence number of all the
              chassis in the system, as reported in the Chassis_Private table in  the  southbound  database.  In
              other  words,  this  timestamp  reflects  the  time  when  the slowest chassis catches up with the
              northbound configuration, which is useful for end-to-end control plane latency measurement.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

     Common options:

       options: map of string-string pairs
              This column provides general key/value settings. The supported options are described  individually
              below.

     Options for configuring OVS BFD:

       These  options  apply  when  ovn-controller  configures  OVS BFD on tunnels interfaces. Please note these
       parameters refer to legacy OVS BFD implementation and not to OVN BFD one.

       options : bfd-min-rx: optional string
              BFD option min-rx value to use when configuring BFD on tunnel interfaces.

       options : bfd-decay-min-rx: optional string
              BFD option decay-min-rx value to use when configuring BFD on tunnel interfaces.

       options : bfd-min-tx: optional string
              BFD option min-tx value to use when configuring BFD on tunnel interfaces.

       options : bfd-mult: optional string
              BFD option mult value to use when configuring BFD on tunnel interfaces.

       options : ignore_chassis_features: optional string
              When set to false, the ovn-northd will evaluate the features supported by each  chassis  and  will
              only activate features that are universally supported by all chassis. This approach is crucial for
              maintaining backward compatibility during an upgrade when the ovn-northd is updated prior  to  the
              ovn-controller. However, if any chassis is poorly managed and the upgrade is unsuccessful, it will
              restrict ovn-northd from activating the new features.

              Alternatively, setting this option to true instructs ovn-northd to bypass the  support  status  of
              features  on  each chassis and to directly implement the latest features. This approach safeguards
              the operation of ovn-northd from being adversely affected  by  a  mismatched  configuration  of  a
              chassis.

              The default setting for this option is false.

       options : mac_prefix: optional string
              Configure a given OUI to be used as prefix when L2 address is dynamically assigned, e.g. 00:11:22

       options : mac_binding_removal_limit: optional string, containing an integer, in range 0 to 4,294,967,295
              MAC  binding  aging  bulk  removal  limit.  This  limits  how  many  rows  can  expire in a single
              transaction. Default value is 0 which is unlimited. When we hit the limit next  batch  removal  is
              delayed by 5 s.

       options : fdb_removal_limit: optional string, containing an integer, in range 0 to 4,294,967,295
              FDB  aging  bulk  removal  limit.  This  limits  how many rows can expire in a single transaction.
              Default value is 0 which is unlimited. When we hit the limit next batch removal is delayed by 5 s.

       options : controller_event: optional string, either true or false
              Value set by the CMS to enable/disable ovn-controller event reporting. Traffic into OVS can  raise
              a  ’controller’  event  that  results  in a Controller_Event being written to the Controller_Event
              table in SBDB. When the CMS has seen the event and taken appropriate action,  it  can  remove  the
              corresponding row in Controller_Event table. The intention is for a CMS to see the events and take
              some sort of action. Please see the Controller_Event table in SBDB. It is possible to associate  a
              meter  to each controller event type in order to not overload the pinctrl thread under heavy load.
              Each event type relies on a meter with a defined name:

              •      empty_lb_backends: event-elb

       options : northd_probe_interval: optional string
              The inactivity probe interval of the connection to the OVN  Northbound  and  Southbound  databases
              from  ovn-northd,  in  milliseconds.  If  the  value is zero, it disables the connection keepalive
              feature.

              If the value is nonzero, then it will be forced to a value of at least 1000 ms.

       options : ic_probe_interval: optional string
              The inactivity probe interval of the connection to the OVN  Northbound  and  Southbound  databases
              from ovn-ic, in milliseconds. If the value is zero, it disables the connection keepalive feature.

              If the value is nonzero, then it will be forced to a value of at least 1000 ms.

       options : nbctl_probe_interval: optional string
              The  inactivity  probe  interval  of  the connection to the OVN Northbound database from ovn-nbctl
              utility, in milliseconds. If the value is zero, it disables the connection keepalive feature.

              If the value is nonzero, then it will be forced to a value of at least 1000 ms.

              If the value is less than zero, then the default inactivity probe interval for ovn-nbctl would  be
              left intact (120000 ms).

       options : northd_trim_timeout: optional string
              When used, this configuration value specifies the time, in milliseconds, since the last ovn-northd
              active operation after which memory trimming is performed. By default this is  set  to  30000  (30
              seconds).

       options : use_logical_dp_groups: optional string
              Note:  This option is deprecated, the only behavior is to always combine logical flows by datapath
              groups. Changing the value or removing this option all toghether will have no effect.

              ovn-northd combines logical flows that differs only by logical datapath into a single logical flow
              with logical datapath group attached.

       options : use_parallel_build: optional string
              If set to true, ovn-northd will attempt to compute logical flows in parallel.

              Parallel  computation  is  enabled  only if the system has 4 or more cores/threads available to be
              used by ovn-northd.

              The default value is false.

       options : ignore_lsp_down: optional string
              If set to false, ARP/ND reply flows for logical switch ports will be installed only if the port is
              up,  i.e. claimed by a Chassis. If set to true, these flows are installed regardless of the status
              of the port, which can result in a situation that ARP request to an IP is resolved even before the
              relevant  VM/container is running. For environments where this is not an issue, setting it to true
              can reduce the load and latency of the control plane. The default value is true.

       options : use_ct_inv_match: optional string
              If set to false, ovn-northd will not use the ct.inv field in any of the logical flow matches.  The
              default  value  is  true.  If  the  NIC supports offloading OVS datapath flows but doesn’t support
              offloading ct_state inv flag, then the datapath flows matching on this flag (either +inv or  -inv)
              will  not  be offloaded. CMS should consider setting use_ct_inv_match to false in such cases. This
              results in a side effect of the invalid packets getting delivered to the  destination  VIF,  which
              otherwise would have been dropped by OVN.

       options : default_acl_drop: optional string
              If set to true., ovn-northd will generate a logical flow to drop all traffic in the ACL stages. By
              default this option is set to false.

       options : debug_drop_domain_id: optional string
              If set to a 8-bit number and if debug_drop_collector_set is also configured, ovn-northd will add a
              sample  action to every logical flow that contains a ’drop’ action. The 8 most significant bits of
              the observation_domain_id field will be those specified in the  debug_drop_domain_id. The 24 least
              significant bits of the observation_domain_id field will be the datapath’s key.

              The observation_point_id will be set to the first 32 bits of the logical flow’s UUID.

       options : debug_drop_collector_set: optional string
              If  set to a 32-bit number ovn-northd will add a sample action to every logical flow that contains
              a ’drop’ action. The sample action will have the specified collector_set_id. The value must  match
              that of the local OVS configuration as described in ovs-actions(7).

       options : use_common_zone: optional string, either true or false
              Default  value  is  false.  If  set  to  true the SNAT and DNAT happens in common zone, instead of
              happening in separate zones, depending on the configuration. However, this option  breaks  traffic
              when  there  is configuration of DGP + LB + SNAT on this LR. The value true should be used only in
              case of HWOL compatibility with GDP.

       options : northd-backoff-interval-ms: optional string
              Maximum interval that the northd incremental engine is delayed by  in  milliseconds.  Setting  the
              value  to  nonzero  delays  the  next  northd  engine  run by the previous run time, capped by the
              specified value. If the value is zero the engine won’t be delayed at all. The  recommended  period
              is smaller than 500 ms, beyond that the latency of SB changes would be very noticeable.

     Options for configuring interconnection route advertisement:

       These  options control how routes are advertised between OVN deployments for interconnection. If enabled,
       ovn-ic  from  different  OVN  deployments  exchanges  routes  between  each  other  through  the   global
       OVN_IC_Southbound  database.  Only  routers  with  ports  connected  to  interconnection transit switches
       participate in route advertisement. For each of these routers, there  are  two  types  of  routes  to  be
       advertised:

       Firstly, the static routes configured in the router are advertised.

       Secondly,  the  networks  configured in the logical router ports that are not on the transit switches are
       advertised. These are considered as directly connected subnets on the router.

       Link local prefixes (IPv4 169.254.0.0/16 and IPv6 FE80::/10) are never advertised.

       The  learned  routes  are  added  to  the  static_routes  column  of  the  Logical_Router   table,   with
       external_ids:ic-learned-route  set  to  the  uuid  of  the  row  in  Route table of the OVN_IC_Southbound
       database.

       options : ic-route-adv: optional string
              A boolean value that enables route advertisement to the global OVN_IC_Southbound database. Default
              is false.

       options : ic-route-learn: optional string
              A boolean value that enables route learning from the global OVN_IC_Southbound database. Default is
              false.

       options : ic-route-adv-default: optional string
              A boolean value that enables advertising default route to the global  OVN_IC_Southbound  database.
              Default is false. This option takes effect only when option ic-route-adv is true.

       options : ic-route-learn-default: optional string
              A  boolean  value  that enables learning default route from the global OVN_IC_Southbound database.
              Default is false. This option takes effect only when option ic-route-learn is true.

       options : ic-route-blacklist: optional string
              A string value contains a list of CIDRs delimited by ",".  A  route  will  not  be  advertised  or
              learned if the route’s prefix belongs to any of the CIDRs listed.

     Connection Options:

       connections: set of Connections
              Database  clients  to  which the Open vSwitch database server should connect or on which it should
              listen, along with options for how these connections should  be  configured.  See  the  Connection
              table for more information.

       ssl: optional SSL
              Global SSL configuration.

     Security Configurations:

       ipsec: boolean
              Tunnel  encryption  configuration.  If  this  column  is  set  to be true, all OVN tunnels will be
              encrypted with IPsec.

     Read-only Options:

       options : max_tunid: optional string
              The maximum supported tunnel ID. Depends on types of encapsulation enabled in the cluster.

Copp TABLE

       This table is used to define control plane protection policies, i.e., associate entries from table  Meter
       to control protocol names.

   Summary:
       name                          string (must be unique within table)
       meters : arp                  optional string
       meters : arp-resolve          optional string
       meters : dhcpv4-opts          optional string
       meters : dhcpv6-opts          optional string
       meters : dns                  optional string
       meters : event-elb            optional string
       meters : icmp4-error          optional string
       meters : icmp6-error          optional string
       meters : igmp                 optional string
       meters : nd-na                optional string
       meters : nd-ns                optional string
       meters : nd-ns-resolve        optional string
       meters : nd-ra-opts           optional string
       meters : tcp-reset            optional string
       meters : bfd                  optional string
       meters : reject               optional string
       meters : svc-monitor          optional string
       external_ids                  map of string-string pairs

   Details:
       name: string (must be unique within table)
              CoPP name.

       meters : arp: optional string
              Rate limiting meter for ARP packets (request/reply) used for learning neighbors.

       meters : arp-resolve: optional string
              Rate limiting meter for packets that require resolving the next-hop (through ARP).

       meters : dhcpv4-opts: optional string
              Rate limiting meter for packets that require adding DHCPv4 options.

       meters : dhcpv6-opts: optional string
              Rate limiting meter for packets that require adding DHCPv6 options.

       meters : dns: optional string
              Rate limiting meter for DNS query packets that need to be replied to.

       meters : event-elb: optional string
              Rate limiting meter for empty load balancer events.

       meters : icmp4-error: optional string
              Rate limiting meter for packets that require replying with an ICMP error.

       meters : icmp6-error: optional string
              Rate limiting meter for packets that require replying with an ICMPv6 error.

       meters : igmp: optional string
              Rate limiting meter for IGMP packets.

       meters : nd-na: optional string
              Rate limiting meter for ND neighbor advertisement packets used for learning neighbors.

       meters : nd-ns: optional string
              Rate limiting meter for ND neighbor solicitation packets used for learning neighbors.

       meters : nd-ns-resolve: optional string
              Rate limiting meter for packets that require resolving the next-hop (through ND).

       meters : nd-ra-opts: optional string
              Rate limiting meter for packets that require adding ND router advertisement options.

       meters : tcp-reset: optional string
              Rate limiting meter for packets that require replying with TCP RST packet.

       meters : bfd: optional string
              Rate limiting meter for BFD packets.

       meters : reject: optional string
              Rate limiting meter for packets that trigger a reject action

       meters : svc-monitor: optional string
              Rate limiting meter for packets that are arriving to service monitor MAC address.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Logical_Switch TABLE

       Each row represents one L2 logical switch.

       There are two kinds of logical switches, that is, ones that fully virtualize the network (overlay logical
       switches) and ones that provide simple connectivity to physical networks (bridged logical switches). They
       work  in  the same way when providing connectivity between logical ports on same chassis, but differently
       when connecting remote logical ports. Overlay logical switches connect remote logical ports  by  tunnels,
       while  bridged  logical switches provide connectivity to remote ports by bridging the packets to directly
       connected physical L2 segments with the help of localnet ports. Each bridged logical switch  has  one  or
       more localnet ports, which have only one special address unknown.

   Summary:
       ports                         set of Logical_Switch_Ports
       load_balancer                 set of weak reference to Load_Balancers
       load_balancer_group           set of Load_Balancer_Groups
       acls                          set of ACLs
       qos_rules                     set of QoSes
       dns_records                   set of weak reference to DNSes
       forwarding_groups             set of Forwarding_Groups
       Naming:
         name                        string
         external_ids : neutron:network_name
                                     optional string
       IP Address Assignment:
         other_config : subnet       optional string
         other_config : exclude_ips  optional string
         other_config : ipv6_prefix  optional string
         other_config : mac_only     optional string, either true or false
         other_config : fdb_age_threshold
                                     optional string, containing an integer, in range 0 to 4,294,967,295
       IP Multicast Snooping Options:
         other_config : mcast_snoop  optional string, either true or false
         other_config : mcast_querier
                                     optional string, either true or false
         other_config : mcast_flood_unregistered
                                     optional string, either true or false
         other_config : mcast_table_size
                                     optional string, containing an integer, in range 1 to 32,766
         other_config : mcast_idle_timeout
                                     optional string, containing an integer, in range 15 to 3,600
         other_config : mcast_query_interval
                                     optional string, containing an integer, in range 1 to 3,600
         other_config : mcast_query_max_response
                                     optional string, containing an integer, in range 1 to 10
         other_config : mcast_eth_src
                                     optional string
         other_config : mcast_ip4_src
                                     optional string
         other_config : mcast_ip6_src
                                     optional string
       Interconnection:
         other_config : interconn-ts
                                     optional string
       Tunnel Key:
         other_config : requested-tnl-key
                                     optional string, containing an integer, in range 1 to 16,777,215
       copp                          optional weak reference to Copp
       Other options:
         other_config : vlan-passthru
                                     optional string, either true or false
         other_config : broadcast-arps-to-all-routers
                                     optional string, either true or false
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       ports: set of Logical_Switch_Ports
              The logical ports connected to the logical switch.

              It is an error for multiple logical switches to include the same logical port.

       load_balancer: set of weak reference to Load_Balancers
              Set of load balancers associated to this logical switch.

       load_balancer_group: set of Load_Balancer_Groups
              Set of load balancers groups associated to this logical switch.

       acls: set of ACLs
              Access control rules that apply to packets within the logical switch.

       qos_rules: set of QoSes
              QoS marking and metering rules that apply to packets within the logical switch.

       dns_records: set of weak reference to DNSes
              This  column  defines  the  DNS  records  to be used for resolving internal DNS queries within the
              logical switch by the native DNS resolver. Please see the DNS table.

       forwarding_groups: set of Forwarding_Groups
              Groups a set of logical port endpoints for traffic going out of the logical switch.

     Naming:

       These columns provide names for the logical switch. From OVN’s perspective, these names have  no  special
       meaning or purpose other than to provide convenience for human interaction with the database. There is no
       requirement for the name to be unique. (For a unique identifier for a logical switch, use its row UUID.)

       (Originally, name was intended to serve the purpose of a human-friendly name, but the Neutron integration
       used it to uniquely identify its own switch object, in the format neutron-uuid. Later on, Neutron started
       propagating the friendly name of a switch  as  external_ids:neutron:network_name.  Perhaps  this  can  be
       cleaned up someday.)

       name: string
              A name for the logical switch.

       external_ids : neutron:network_name: optional string
              Another name for the logical switch.

     IP Address Assignment:

       These options control automatic IP address management (IPAM) for ports attached to the logical switch. To
       enable IPAM for IPv4, set other_config:subnet and optionally other_config:exclude_ips. To enable IPAM for
       IPv6, set other_config:ipv6_prefix. IPv4 and IPv6 may be enabled together or separately.

       To  request  dynamic  address  assignment for a particular port, use the dynamic keyword in the addresses
       column of the port’s Logical_Switch_Port row. This requests both an IPv4 and an IPv6 address, if IPAM for
       IPv4 and IPv6 are both enabled.

       other_config : subnet: optional string
              Set  this  to an IPv4 subnet, e.g. 192.168.0.0/24, to enable ovn-northd to automatically assign IP
              addresses within that subnet.

       other_config : exclude_ips: optional string
              To exclude some addresses from automatic IP address management, set this to a  list  of  the  IPv4
              addresses  or  ..-delimited ranges to exclude. The addresses or ranges should be a subset of those
              in other_config:subnet.

              Whether listed or not, ovn-northd will never allocate the first or last address in a subnet,  such
              as 192.168.0.0 or 192.168.0.255 in 192.168.0.0/24.

              Examples:

              •      192.168.0.2 192.168.0.10192.168.0.4 192.168.0.30..192.168.0.60 192.168.0.110..192.168.0.120192.168.0.110..192.168.0.120 192.168.0.25..192.168.0.30 192.168.0.144

       other_config : ipv6_prefix: optional string
              Set  this to an IPv6 prefix to enable ovn-northd to automatically assign IPv6 addresses using this
              prefix. The assigned IPv6 address will be generated using the IPv6  prefix  and  the  MAC  address
              (converted  to  an  IEEE  EUI64  identifier) of the port. The IPv6 prefix defined here should be a
              valid IPv6 address ending with ::.

              Examples:

              •      aef0::bef0:1234:a890:5678::8230:5678::

       other_config : mac_only: optional string, either true or false
              Value used to request to assign L2 address only if neither subnet nor ipv6_prefix are specified

       other_config : fdb_age_threshold: optional string, containing an integer, in range 0 to 4,294,967,295
              FDB aging threshold value in seconds. FDB exceeding this timeout will  be  automatically  removed.
              The value defaults to 0, which means disabled.

     IP Multicast Snooping Options:

       These  options  control IP Multicast Snooping configuration of the logical switch. To enable IP Multicast
       Snooping   set   other_config:mcast_snoop   to   true.   To   enable    IP    Multicast    Querier    set
       other_config:mcast_querier  to  true.  If  IP Multicast Querier is enabled other_config:mcast_eth_src and
       other_config:mcast_ip4_src must be set.

       other_config : mcast_snoop: optional string, either true or false
              Enables/disables IP Multicast Snooping on the logical switch. Default: false.

       other_config : mcast_querier: optional string, either true or false
              Enables/disables  IP   Multicast   Querier   on   the   logical   switch.   Only   applicable   if
              other_config:mcast_snoop is enabled. Default: true.

       other_config : mcast_flood_unregistered: optional string, either true or false
              Determines  whether  unregistered  multicast  traffic should be flooded or not. Only applicable if
              other_config:mcast_snoop is enabled. Default: false.

       other_config : mcast_table_size: optional string, containing an integer, in range 1 to 32,766
              Number of multicast groups to be stored. Default: 2048.

       other_config : mcast_idle_timeout: optional string, containing an integer, in range 15 to 3,600
              Configures the IP Multicast Snooping group idle timeout (in seconds). Default: 300 seconds.

       other_config : mcast_query_interval: optional string, containing an integer, in range 1 to 3,600
              Configures  the  IP  Multicast  Querier  interval   between   queries   (in   seconds).   Default:
              other_config:mcast_idle_timeout / 2.

       other_config : mcast_query_max_response: optional string, containing an integer, in range 1 to 10
              Configures  the  value  of  the  "max-response"  field  in the multicast queries originated by the
              logical switch. Default: 1 second.

       other_config : mcast_eth_src: optional string
              Configures the source Ethernet address for queries originated by the logical switch.

       other_config : mcast_ip4_src: optional string
              Configures the source IPv4 address for queries originated by the logical switch.

       other_config : mcast_ip6_src: optional string
              Configures the source IPv6 address for queries originated by the logical switch.

     Interconnection:

       other_config : interconn-ts: optional string
              The name of corresponding transit switch in  OVN_IC_Northbound  database.  This  kind  of  logical
              switch is created and controlled by ovn-ic.

     Tunnel Key:

       other_config : requested-tnl-key: optional string, containing an integer, in range 1 to 16,777,215
              Configures  the  datapath  tunnel  key  for the logical switch. Usually this is not needed because
              ovn-northd will assign an unique key for each datapath by itself. However, if  it  is  configured,
              ovn-northd  honors  the  configured value. The typical use case is for interconnection: the tunnel
              keys for transit switches need to be unique  globally,  so  they  are  maintained  in  the  global
              OVN_IC_Southbound  database, and ovn-ic simply syncs the value from OVN_IC_Southbound through this
              config.

       copp: optional weak reference to Copp
              The  control  plane  protection  policy  from  table  Copp  used  for  metering  packets  sent  to
              ovn-controller from ports of this logical switch.

     Other options:

       other_config : vlan-passthru: optional string, either true or false
              Determines  whether  VLAN  tagged  incoming  traffic  should  be  allowed. Note that this may have
              security implications when enabled for a logical  switch  with  a  tag=0  localnet  port.  If  not
              properly  isolated from other localnet ports, fabric traffic that belongs to other tagged networks
              may be passed through such a port.

       other_config : broadcast-arps-to-all-routers: optional string, either true or false
              Determines whether arp requests and ipv6 neighbor solicitations should be sent to all routers  and
              other  switchports  (default) or if it should only be sent to switchports where the ip/mac address
              is unknown. Setting this to false can significantly reduce the load  if  the  logical  switch  can
              receive arp requests for ips it does not know about. However setting this to false also means that
              garps are no longer forwarded to all routers and therefor the mac bindings of the routers  are  no
              longer updated.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Logical_Switch_Port TABLE

       A port within an L2 logical switch.

   Summary:
       Core Features:
         name                        string (must be unique within table)
         type                        string
       Options:
         options                     map of string-string pairs
         Options for router ports:
            options : router-port    optional string
            options : nat-addresses  optional string
            options : exclude-lb-vips-from-garp
                                     optional string
            options : arp_proxy      optional string
            options : enable_router_port_acl
                                     optional string, either true or false
         Options for localnet ports:
            options : network_name   optional string
            options : ethtype        optional string
            options : localnet_learn_fdb
                                     optional string, either true or false
         Options for l2gateway ports:
            options : network_name   optional string
            options : l2gateway-chassis
                                     optional string
         Options for vtep ports:
            options : vtep-physical-switch
                                     optional string
            options : vtep-logical-switch
                                     optional string
         VMI (or VIF) Options:
            options : requested-chassis
                                     optional string
            options : activation-strategy
                                     optional string
            options : iface-id-ver   optional string
            options : qos_min_rate   optional string
            options : qos_max_rate   optional string
            options : qos_burst      optional string
            options : hostname       optional string
            VIF Plugging Options:
              options : vif-plug-type
                                     optional string
              options : vif-plug-mtu-request
                                     optional string
         Virtual port Options:
            options : virtual-ip     optional string
            options : virtual-parents
                                     optional string
         IP Multicast Snooping Options:
            options : mcast_flood    optional string, either true or false
            options : mcast_flood_reports
                                     optional string, either true or false
       Containers:
         parent_name                 optional string
         tag_request                 optional integer, in range 0 to 4,095
         tag                         optional integer, in range 1 to 4,095
       Port State:
         up                          optional boolean
         enabled                     optional boolean
       Addressing:
         addresses                   set of strings
         dynamic_addresses           optional string
         port_security               set of strings
       DHCP:
         dhcpv4_options              optional weak reference to DHCP_Options
         dhcpv6_options              optional weak reference to DHCP_Options
       mirror_rules                  set of weak reference to Mirrors
       ha_chassis_group              optional HA_Chassis_Group
       Naming:
         external_ids : neutron:port_name
                                     optional string
       Tunnel Key:
         options : requested-tnl-key
                                     optional string, containing an integer, in range 1 to 32,767
       Common Columns:
         external_ids                map of string-string pairs

   Details:
     Core Features:

       name: string (must be unique within table)
              The logical port name.

              For entities (VMs or containers) that are spawned in the hypervisor, the name used here must match
              those used in the external_ids:iface-id in the Open_vSwitch database’s  Interface  table,  because
              hypervisors  use  external_ids:iface-id  as a lookup key to identify the network interface of that
              entity.

              For containers that share a VIF  within  a  VM,  the  name  can  be  any  unique  identifier.  See
              Containers, below, for more information.

              A logical switch port may not have the same name as a logical router port, but the database schema
              cannot enforce this.

       type: string
              Specify a type for this logical  port.  Logical  ports  can  be  used  to  model  other  types  of
              connectivity into an OVN logical switch. The following types are defined:

              (empty string)
                     A VM (or VIF) interface.

              router A  connection  to  a logical router. The value of options:router-port specifies the name of
                     the Logical_Router_Port to which this logical switch port is connected.

              localnet
                     A connection to a locally accessible network from  ovn-controller  instances  that  have  a
                     corresponding  bridge  mapping. A logical switch can have multiple localnet ports attached.
                     This type is used to model direct connectivity to existing networks.  In  this  case,  each
                     chassis  should  have  a  mapping for one of the physical networks only. Note: nothing said
                     above implies that a chassis cannot be plugged to multiple physical  networks  as  long  as
                     they belong to different switches.

              localport
                     A  connection to a local VIF. Traffic that arrives on a localport is never forwarded over a
                     tunnel to another chassis. These ports are present on  every  chassis  and  have  the  same
                     address  in  all  of them. This is used to model connectivity to local services that run on
                     every hypervisor.

              l2gateway
                     A connection to a physical network.

              vtep   A port to a logical switch on a VTEP gateway.

              external
                     Represents a logical port which is external and not having an OVS port in  the  integration
                     bridge. OVN will never receive any traffic from this port or send any traffic to this port.
                     OVN can support native services like DHCPv4/DHCPv6/DNS for this port.  If  ha_chassis_group
                     is  defined, ovn-controller running in the master chassis of the HA chassis group will bind
                     this port to provide these native services. It is expected  that  this  port  belong  to  a
                     bridged logical switch (with a localnet port).

                     It  is recommended to use the same HA chassis group for all the external ports of a logical
                     switch. Otherwise, the physical switch might see MAC  flap  issue  when  different  chassis
                     provide  the  native  services.  For  example when supporting native DHCPv4 service, DHCPv4
                     server mac (configured in options:server_mac column in table DHCP_Options) originating from
                     different ports can cause MAC flap issue. The MAC of the logical router IP(s) can also flap
                     if the same HA chassis group is not set for all the external ports of a logical switch.

                     Below are some of the use cases where external ports can be used.

                     •      VMs connected to SR-IOV nics - Traffic from these VMs by passes the kernel stack and
                            local ovn-controller do not bind these ports and cannot serve the native services.

                     •      When CMS supports provisioning baremetal servers.

              virtual
                     Represents a logical port which does not have an OVS port in the integration bridge and has
                     a virtual ip configured in the options:virtual-ip column. This virtual ip can  move  around
                     between the logical ports configured in the options:virtual-parents column.

                     One of the use case where virtual ports can be used is.

                     •      The  virtual  ip represents a load balancer vip and the virtual parents provide load
                            balancer service in an active-standby setup with the active  virtual  parent  owning
                            the virtual ip.

              remote A  remote  port  is  to  model a port that resides remotely on another OVN, which is on the
                     other side of a transit logical switch for OVN interconnection.  This  type  of  ports  are
                     created  by  ovn-ic  instead  of  by  CMS.  Any  change  to  the port will be automatically
                     overwritten by ovn-ic.

     Options:

       options: map of string-string pairs
              This column provides key/value settings specific to  the  logical  port  type.  The  type-specific
              options are described individually below.

     Options for router ports:

       These options apply when type is router.

       options : router-port: optional string
              Required. The name of the Logical_Router_Port to which this logical switch port is connected.

       options : nat-addresses: optional string
              This  is used to send gratuitous ARPs for SNAT and DNAT IP addresses via the localnet port that is
              attached to the same logical switch as this type router  port.  This  option  is  specified  on  a
              logical  switch  port  that  is  connected  to  a gateway router, or a logical switch port that is
              connected to a distributed gateway port on a logical router.

              This must take one of the following forms:

              router Gratuitous ARPs will be sent for all SNAT and DNAT external IP addresses and for  all  load
                     balancer  IP  addresses  defined  on  the  options:router-port’s  logical router, using the
                     options:router-port’s MAC address.

                     This form of options:nat-addresses is valid for logical switch ports where  options:router-
                     port is the name of a port on a gateway router, or the name of a distributed gateway port.

                     Supported only in OVN 2.8 and later. Earlier versions required NAT addresses to be manually
                     synchronized.

              Ethernet address followed by one or more IPv4 addresses
                     Example: 80:fa:5b:06:72:b7 158.36.44.22 158.36.44.24. This would result  in  generation  of
                     gratuitous  ARPs  for  IP  addresses  158.36.44.22  and  158.36.44.24 with a MAC address of
                     80:fa:5b:06:72:b7.

                     This  form  of  options:nat-addresses  is  only  valid  for  logical  switch  ports   where
                     options:router-port is the name of a port on a gateway router.

       options : exclude-lb-vips-from-garp: optional string
              If  options:nat-addresses  is  set  to  router, Gratuitous ARPs will be sent for all SNAT and DNAT
              external  IP  addresses  defined  on  the  options:router-port’s   logical   router,   using   the
              options:router-port’s MAC address, not cosidering configured load balancers.

       options : arp_proxy: optional string
              Optional.  A  list  of  MAC  and  addresses/cidrs or just addresses/cidrs that this logical switch
              router  port  will  reply  to   ARP/NDP   requests.   Examples:   169.254.239.254   169.254.239.2,
              0a:58:a9:fe:01:01    169.254.239.254    169.254.239.2   169.254.238.0/24,   fd7b:6b4d:7b25:d22f::1
              fd7b:6b4d:7b25:d22f::2,  0a:58:a9:fe:01:01   fd7b:6b4d:7b25:d22f::0/64.   Theoptions:router-port’s
              logical  router  should have a route to forward packets sent to configured proxy ARP MAC/IPs to an
              appropriate destination.

       options : enable_router_port_acl: optional string, either true or false
              Optional. Enable conntrack for the router port whose peer  is  l3dgw_port  if  set  to  true.  The
              default value is false.

     Options for localnet ports:

       These options apply when type is localnet.

       options : network_name: optional string
              Required.  The  name  of the network to which the localnet port is connected. Each hypervisor, via
              ovn-controller, uses its local configuration to determine exactly how to connect to  this  locally
              accessible network, if at all.

       options : ethtype: optional string
              Optional.  VLAN  EtherType  field  value  for encapsulating VLAN headers. Supported values: 802.1q
              (default), 802.1ad.

       options : localnet_learn_fdb: optional string, either true or false
              Optional. Allows localnet port to learn MACs and store them in FDB  table  if  set  to  true.  The
              default value is false.

     Options for l2gateway ports:

       These options apply when type is l2gateway.

       options : network_name: optional string
              Required.  The  name  of the network to which the l2gateway port is connected. The L2 gateway, via
              ovn-controller, uses its local configuration to determine exactly how to connect to this network.

       options : l2gateway-chassis: optional string
              Required. The chassis on which the l2gateway logical  port  should  be  bound  to.  ovn-controller
              running on the defined chassis will connect this logical port to the physical network.

     Options for vtep ports:

       These options apply when type is vtep.

       options : vtep-physical-switch: optional string
              Required. The name of the VTEP gateway.

       options : vtep-logical-switch: optional string
              Required. A logical switch name connected by the VTEP gateway.

     VMI (or VIF) Options:

       These options apply to logical ports with type having (empty string)

       options : requested-chassis: optional string
              If  set,  identifies  a  specific chassis (by name or hostname) that is allowed to bind this port.
              Using this option will prevent thrashing between two chassis trying to bind the same port during a
              live  migration.  It  can  also prevent similar thrashing due to a mis-configuration, if a port is
              accidentally created on more than one chassis.

              If set to a comma separated list, the first entry identifies the main chassis and the rest are one
              or more additional chassis that are allowed to bind the same port.

              When  multiple  chassis  are  set for the port, and the logical switch is connected to an external
              network through a localnet port, tunneling is enforced for  the  port  to  guarantee  delivery  of
              packets  directed  to the port to all its locations. This has MTU implications because the network
              used for tunneling must have MTU larger than localnet for stable connectivity.

              If the same host co-hosts more than one controller instance  (either  belonging  to  the  same  or
              separate  clusters),  special attention should be given to consistently using unique chassis names
              used in this option. It is advised that chassis names - and not host names -  are  used  for  this
              option.

       options : activation-strategy: optional string
              If  used  with multiple chassis set in requested-chassis, specifies an activation strategy for all
              additional chassis. By default, no activation strategy is used, meaning additional port  locations
              are  immediately available for use. When set to "rarp", the port is blocked for ingress and egress
              communication until a RARP packet is sent from a new location. The "rarp" strategy  is  useful  in
              live migration scenarios for virtual machines.

       options : iface-id-ver: optional string
              If set, this port will be bound by ovn-controller only if this same key and value is configured in
              the external_ids column in the Open_vSwitch database’s Interface table.

       options : qos_min_rate: optional string
              If set, indicates the minimum guaranteed rate available for data  sent  from  this  interface,  in
              bit/s.

       options : qos_max_rate: optional string
              If  set,  indicates the maximum rate for data sent from this interface, in bit/s. The traffic will
              be shaped according to this limit.

       options : qos_burst: optional string
              If set, indicates the maximum burst size for data sent from this interface, in bits.

       options : hostname: optional string
              If set, indicates the DHCPv4 option "Hostname" (option code 12) associated for this Logical Switch
              Port.  If DHCPv4 is enabled for this Logical Switch Port, hostname dhcp option will be included in
              DHCP reply.

     VIF Plugging Options:

       options : vif-plug-type: optional string
              If set, OVN will attempt to perform plugging of this VIF. In order to get this port plugged by the
              OVN  controller,  OVN must be built with support for VIF plugging. The default behavior is for the
              CMS to do the VIF plugging. Each VIF plug provider have their own options namespaced by name,  for
              example "vif-plug:representor:key". Please refer to the VIF plug provider documentation located in
              Documentation/topics/vif-plug-providers/ for more information.

       options : vif-plug-mtu-request: optional string
              Requested MTU for plugged interfaces. When set the OVN controller will fill the mtu_request column
              of the Open vSwitch database’s Interface table. This in turn will make OVS vswitchd update the MTU
              of the linked interface.

     Virtual port Options:

       These options apply when type is virtual.

       options : virtual-ip: optional string
              This option represents the virtual IPv4 address.

       options : virtual-parents: optional string
              This options represents a set of logical port names (with in the same logical  switch)  which  can
              own  the virtual ip configured in the options:virtual-ip. All these virtual parents should add the
              virtual ip in the port_security if port security addressed are enabled.

     IP Multicast Snooping Options:

       These options apply when the port is part of a logical switch which has other_config :mcast_snoop set  to
       true.

       options : mcast_flood: optional string, either true or false
              If  set  to true, multicast packets (except reports) are unconditionally forwarded to the specific
              port. Default: false.

       options : mcast_flood_reports: optional string, either true or false
              If set to true, multicast reports are unconditionally forwarded to  the  specific  port.  Default:
              false.

     Containers:

       When  a  large  number of containers are nested within a VM, it may be too expensive to dedicate a VIF to
       each container. OVN can use VLAN tags to support such cases. Each container is assigned  a  VLAN  ID  and
       each  packet  that  passes  between  the  hypervisor and the VM is tagged with the appropriate ID for the
       container. Such VLAN IDs never appear on a physical wire, even inside a  tunnel,  so  they  need  not  be
       unique except relative to a single VM on a hypervisor.

       These  columns  are  used  for  VIFs  that represent nested containers using shared VIFs. For VMs and for
       containers that have dedicated VIFs, they are empty.

       parent_name: optional string
              The VM interface through which the nested container sends its network traffic. This must match the
              name  column  for  some  other  Logical_Switch_Port.  Note:  for performance of the OVN Southbound
              database conditional monitoring, unlike for regular VIFs,  ovn-controller  will  register  to  get
              updates  about  all  OVN  Southbound database Port_Binding table records that correspond to nested
              container ports even if external_ids:ovn-monitor-all is set to false.  See  ovn-controller(8)  for
              more information.

       tag_request: optional integer, in range 0 to 4,095
              The  VLAN  tag  in the network traffic associated with a container’s network interface. The client
              can request ovn-northd to allocate a tag that is unique within the  scope  of  a  specific  parent
              (specified  in parent_name) by setting a value of 0 in this column. The allocated value is written
              by ovn-northd in the tag column. (Note that these  tags  are  allocated  and  managed  locally  in
              ovn-northd,  so  they  cannot be reconstructed in the event that the database is lost.) The client
              can also request a specific non-zero tag and ovn-northd will honor it and copy that value  to  the
              tag column.

              When  type is set to localnet or l2gateway, this can be set to indicate that the port represents a
              connection to a specific VLAN on a locally accessible network.  The  VLAN  ID  is  used  to  match
              incoming traffic and is also added to outgoing traffic.

       tag: optional integer, in range 1 to 4,095
              The VLAN tag allocated by ovn-northd based on the contents of the tag_request column.

     Port State:

       up: optional boolean
              This column is populated by ovn-northd, rather than by the CMS plugin as is most of this database.
              When a logical port is bound to a physical location in the OVN Southbound database Binding  table,
              ovn-northd  sets  this column to true; otherwise, or if the port becomes unbound later, it sets it
              to false. If this column is empty, the port is not considered up. This allows the CMS to wait  for
              a  VM’s  (or  container’s)  networking  to become active before it allows the VM (or container) to
              start.

              Logical ports of router type are an exception to this rule. They are considered to be  always  up,
              that is this column is always set to true.

       enabled: optional boolean
              This column is used to administratively set port state. If this column is empty or is set to true,
              the port is enabled. If this column is set to false, the port is disabled. A disabled port has all
              ingress and egress traffic dropped.

     Addressing:

       addresses: set of strings
              Addresses owned by the logical port.

              Each element in the set must take one of the following forms:

              Ethernet address followed by zero or more IPv4 or IPv6 addresses (or both)
                     An  Ethernet  address defined is owned by the logical port. Like a physical Ethernet NIC, a
                     logical port ordinarily has a single fixed Ethernet address.

                     When a OVN logical switch processes a unicast Ethernet frame whose destination MAC  address
                     is  in  a  logical  port’s  addresses column, it delivers it only to that port, as if a MAC
                     learning process had learned that MAC address on the port.

                     If IPv4 or IPv6 address(es) (or both) are defined, it indicates that the logical port  owns
                     the given IP addresses.

                     If IPv4 address(es) are defined, the OVN logical switch uses this information to synthesize
                     responses to ARP requests without traversing the physical network. The OVN  logical  router
                     connected  to  the  logical  switch,  if  any,  uses  this information to avoid issuing ARP
                     requests for logical switch ports.

                     Note that the order here is important. The Ethernet address must be listed  before  the  IP
                     address(es) if defined.

                     Examples:

                     80:fa:5b:06:72:b7
                            This indicates that the logical port owns the above mac address.

                     80:fa:5b:06:72:b7 10.0.0.4 20.0.0.4
                            This indicates that the logical port owns the mac address and two IPv4 addresses.

                     80:fa:5b:06:72:b7 fdaa:15f2:72cf:0:f816:3eff:fe20:3f41
                            This indicates that the logical port owns the mac address and 1 IPv6 address.

                     80:fa:5b:06:72:b7 10.0.0.4 fdaa:15f2:72cf:0:f816:3eff:fe20:3f41
                            This  indicates  that the logical port owns the mac address and 1 IPv4 address and 1
                            IPv6 address.

              unknown
                     This indicates that the logical port has an unknown set of Ethernet addresses. When an  OVN
                     logical  switch  processes a unicast Ethernet frame whose destination MAC address is not in
                     any logical port’s addresses column, it delivers it to the port (or ports) whose  addresses
                     columns include unknown.

              dynamic
                     Use  dynamic  to  make  ovn-northd generate a globally unique MAC address, choose an unused
                     IPv4 address with the logical port’s subnet (if other_config:subnet is set  in  the  port’s
                     Logical_Switch),    and   generate   an   IPv6   address   from   the   MAC   address   (if
                     other_config:ipv6_prefix is set in the port’s Logical_Switch) and store them in the  port’s
                     dynamic_addresses column.

                     Only one element containing dynamic may appear in addresses.

              dynamic ip
              dynamic ipv6
              dynamic ip ipv6
                   These  act  like dynamic alone but specify particular IPv4 or IPv6 addresses to use. OVN IPAM
                   will still automatically allocate the other address  if  configured  appropriately.  Example:
                   dynamic 192.168.0.1 2001::1.

              mac dynamic
                   This  acts  like  dynamic  alone but specifies a particular MAC address to use. OVN IPAM will
                   still automatically allocate IPv4 or IPv6 addresses, or both,  if  configured  appropriately.
                   Example: 80:fa:5b:06:72:b7 dynamic

              router
                   Accepted only when type is router. This indicates that the Ethernet, IPv4, and IPv6 addresses
                   for this logical switch port should be obtained from the connected logical  router  port,  as
                   specified by router-port in options.

                   The  resulting  addresses  are  used to populate the logical switch’s destination lookup, and
                   also for the logical switch to generate ARP and ND replies.

                   If the connected logical router port has a distributed gateway port specified and the logical
                   router  has  rules  specified in nat with external_mac, then those addresses are also used to
                   populate the switch’s destination lookup.

                   Supported only in OVN 2.7 and  later.  Earlier  versions  required  router  addresses  to  be
                   manually synchronized.

       dynamic_addresses: optional string
              Addresses  assigned  to  the  logical  port  by  ovn-northd, if dynamic is specified in addresses.
              Addresses will be of the same format as those  that  populate  the  addresses  column.  Note  that
              dynamically  assigned  addresses are constructed and managed locally in ovn-northd, so they cannot
              be reconstructed in the event that the database is lost.

       port_security: set of strings
              This column controls the addresses from which the host attached to the logical port (``the host’’)
              is allowed to send packets and to which it is allowed to receive packets. If this column is empty,
              all addresses are permitted.

              Each element in the set must begin with one Ethernet address. This  would  restrict  the  host  to
              sending packets from and receiving packets to the ethernet addresses defined in the logical port’s
              port_security column. It also restricts the inner source MAC addresses that the host may  send  in
              ARP  and  IPv6  Neighbor  Discovery  packets.  The  host  is  always allowed to receive packets to
              multicast and broadcast Ethernet addresses.

              Each element in the set may additionally contain one or more IPv4 or  IPv6  addresses  (or  both),
              with  optional  masks. If a mask is given, it must be a CIDR mask. In addition to the restrictions
              described for Ethernet addresses above, such an element restricts the IPv4 or IPv6 addresses  from
              which  the  host may send and to which it may receive packets to the specified addresses. A masked
              address, if the host part is zero, indicates that the host is allowed to use any  address  in  the
              subnet;  if  the  host  part  is  nonzero,  the  mask  simply indicates the size of the subnet. In
              addition:

              •      If any IPv4 address is given, the host is also allowed to receive packets to the IPv4 local
                     broadcast address 255.255.255.255 and to IPv4 multicast addresses (224.0.0.0/4). If an IPv4
                     address with a mask is given, the host is also allowed to receive packets to the  broadcast
                     address in that specified subnet.

                     If  any  IPv4  address is given, the host is additionally restricted to sending ARP packets
                     with the specified source IPv4 address. (RARP is not restricted.)

              •      If any IPv6 address is given, the host is also allowed to receive packets to IPv6 multicast
                     addresses (ff00::/8).

                     If  any IPv6 address is given, the host is additionally restricted to sending IPv6 Neighbor
                     Discovery Solicitation or Advertisement packets with the specified source address  or,  for
                     solicitations, the unspecified address.

              If  an  element includes an IPv4 address, but no IPv6 addresses, then IPv6 traffic is not allowed.
              If an element includes an IPv6 address, but no IPv4 address, then IPv4  and  ARP  traffic  is  not
              allowed.

              This  column  uses  the  same  lexical syntax as the match column in the OVN Southbound database’s
              Pipeline table. Multiple addresses within an element may be space or comma separated.

              This column is provided as a convenience to cloud management systems, but all of the features that
              it implements can be implemented as ACLs using the ACL table.

              Examples:

              80:fa:5b:06:72:b7
                     The  host  may  send  traffic from and receive traffic to the specified MAC address, and to
                     receive traffic to Ethernet multicast and broadcast addresses, but not otherwise. The  host
                     may  not  send  ARP or IPv6 Neighbor Discovery packets with inner source Ethernet addresses
                     other than the one specified.

              80:fa:5b:06:72:b7 192.168.1.10/24
                     This adds further restrictions to the first example. The host may send IPv4 packets from or
                     receive  IPv4 packets to only 192.168.1.10, except that it may also receive IPv4 packets to
                     192.168.1.255 (based on the subnet mask), 255.255.255.255, and any address in  224.0.0.0/4.
                     The  host  may not send ARPs with a source Ethernet address other than 80:fa:5b:06:72:b7 or
                     source IPv4 address other than 192.168.1.10. The host may not  send  or  receive  any  IPv6
                     (including IPv6 Neighbor Discovery) traffic.

              "80:fa:5b:12:42:ba", "80:fa:5b:06:72:b7 192.168.1.10/24"
                     The  host  may send traffic from and receive traffic to the specified MAC addresses, and to
                     receive traffic to Ethernet multicast and broadcast addresses, but not otherwise. With  MAC
                     80:fa:5b:12:42:ba,  the  host  may send traffic from and receive traffic to any L3 address.
                     With MAC 80:fa:5b:06:72:b7, the host may send IPv4 packets from or receive IPv4 packets  to
                     only  192.168.1.10, except that it may also receive IPv4 packets to 192.168.1.255 (based on
                     the subnet mask), 255.255.255.255, and any address in 224.0.0.0/4. The host may not send or
                     receive any IPv6 (including IPv6 Neighbor Discovery) traffic.

     DHCP:

       dhcpv4_options: optional weak reference to DHCP_Options
              This column defines the DHCPv4 Options to be included by the ovn-controller when it replies to the
              DHCPv4 requests. Please see the DHCP_Options table.

       dhcpv6_options: optional weak reference to DHCP_Options
              This column defines the DHCPv6 Options to be included by the ovn-controller when it replies to the
              DHCPv6 requests. Please see the DHCP_Options table.

       mirror_rules: set of weak reference to Mirrors
              Mirror rules that apply to logical switch port which is the source. Please see the Mirror table.

       ha_chassis_group: optional HA_Chassis_Group
              References  a  row  in  the  OVN Northbound database’s HA_Chassis_Group table. It indicates the HA
              chassis group to use if the type is set to external. If type  is  not  external,  this  column  is
              ignored.

     Naming:

       external_ids : neutron:port_name: optional string
              This  column  gives an optional human-friendly name for the port. This name has no special meaning
              or purpose other than to provide convenience for human interaction with the northbound database.

              Neutron copies this from its own port object’s name. (Neutron ports do  are  not  assigned  human-
              friendly names by default, so it will often be empty.)

     Tunnel Key:

       options : requested-tnl-key: optional string, containing an integer, in range 1 to 32,767
              Configures the port binding tunnel key for the port. Usually this is not needed because ovn-northd
              will assign an unique key for each port by itself. However, if it is configured, ovn-northd honors
              the  configured  value.  The typical use case is for interconnection: the tunnel keys for ports on
              transit  switches  need  to  be  unique  globally,  so  they  are   maintained   in   the   global
              OVN_IC_Southbound  database, and ovn-ic simply syncs the value from OVN_IC_Southbound through this
              config.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

              The ovn-northd program copies all these pairs into the external_ids  column  of  the  Port_Binding
              table in OVN_Southbound database.

Forwarding_Group TABLE

       Each row represents one forwarding group.

   Summary:
       name                          string
       vip                           string
       vmac                          string
       liveness                      boolean
       child_port                    set of 1 or more strings
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: string
              A name for the forwarding group. This name has no special meaning or purpose other than to provide
              convenience for human interaction with the ovn-nb database.

       vip: string
              The virtual IP address assigned to the forwarding group. It will respond with  vmac  when  an  ARP
              request is sent for vip.

       vmac: string
              The virtual MAC address assigned to the forwarding group.

       liveness: boolean
              If set to true, liveness is enabled for child ports otherwise it is disabled.

       child_port: set of 1 or more strings
              List of child ports in the forwarding group.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Address_Set TABLE

       Each row in this table represents a named set of addresses. An address set may contain Ethernet, IPv4, or
       IPv6 addresses with optional bitwise or CIDR masks. Address set may ultimately be used in ACLs to compare
       against  fields such as ip4.src or ip6.src. A single address set must contain addresses of the same type.
       As an example, the following would create an address set with three IP addresses:

             ovn-nbctl create Address_Set name=set1 addresses=’10.0.0.1 10.0.0.2 10.0.0.3’

       Address sets may be used in the match column of the ACL table. For syntax information, see the details of
       the  expression  language  used  for  the  match  column  in the Logical_Flow table of the OVN_Southbound
       database.

   Summary:
       name                          string (must be unique within table)
       addresses                     set of strings
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: string (must be unique within table)
              A name for the address set. Names are ASCII and must match [a-zA-Z_.][a-zA-Z_.0-9]*.

       addresses: set of strings
              The set of addresses in string form.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Port_Group TABLE

       Each row in this table represents a named group of logical switch ports.

       Port groups may be used in the match column of the ACL table. For syntax information, see the details  of
       the  expression  language  used  for  the  match  column  in the Logical_Flow table of the OVN_Southbound
       database.

       For each port group, there are two address sets generated to the Address_Set table of the  OVN_Southbound
       database,  containing  the IP addresses of the group of ports, one for IPv4, and the other for IPv6, with
       name being the name of the Port_Group followed by a suffix _ip4 for IPv4 and _ip6 for IPv6. The generated
       address  sets  can  be used in the same way as regular address sets in the match column of the ACL table.
       For syntax information, see the details of the expression language used  for  the  match  column  in  the
       Logical_Flow table of the OVN_Southbound database.

   Summary:
       name                          string (must be unique within table)
       ports                         set of weak reference to Logical_Switch_Ports
       acls                          set of ACLs
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: string (must be unique within table)
              A name for the port group. Names are ASCII and must match [a-zA-Z_.][a-zA-Z_.0-9]*.

       ports: set of weak reference to Logical_Switch_Ports
              The logical switch ports belonging to the group in uuids.

       acls: set of ACLs
              Access  control  rules  that apply to the port group. Applying an ACL to a port group has the same
              effect as applying the ACL to all logical lswitches that the ports of the port group belong to.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Load_Balancer TABLE

       Each row represents one load balancer.

   Summary:
       name                          string
       vips                          map of string-string pairs
       protocol                      optional string, one of sctp, tcp, or udp
       Health Checks:
         health_check                set of Load_Balancer_Health_Checks
         ip_port_mappings            map of string-string pairs
       selection_fields              set of strings, one of eth_dst, eth_src, ip_dst, ip_src, tp_dst, or tp_src
       Common Columns:
         external_ids                map of string-string pairs
       Load_Balancer options:
         options : reject            optional string, either true or false
         options : hairpin_snat_ip   optional string
         options : skip_snat         optional string
         options : add_route         optional string
         options : neighbor_responder
                                     optional string
         options : template          optional string
         options : address-family    optional string
         options : affinity_timeout  optional string
         options : ct_flush          optional string, either true or false

   Details:
       name: string
              A name for the load balancer. This name has no special meaning or purpose other  than  to  provide
              convenience for human interaction with the ovn-nb database.

       vips: map of string-string pairs
              A  map of virtual IP addresses (and an optional port number with : as a separator) associated with
              this load balancer and their corresponding endpoint IP addresses (and optional port numbers with :
              as  separators)  separated  by commas. If the destination IP address (and port number) of a packet
              leaving a container or a VM matches the virtual IP address (and port number) provided  here  as  a
              key, then OVN will statefully replace the destination IP address by one of the provided IP address
              (and port number) in this map as  a  value.  IPv4  and  IPv6  addresses  are  supported  for  load
              balancing;  however a VIP of one address family may not be mapped to a destination IP address of a
              different family. If specifying an IPv6 address with a port, the address portion must be  enclosed
              in  square  brackets. Examples for keys are "192.168.1.4" and "[fd0f::1]:8800". Examples for value
              are "10.0.0.1, 10.0.0.2" and "20.0.0.10:8800, 20.0.0.11:8800".

              When the Load_Balancer is added to the logical_switch, the VIP has to be  in  a  different  subnet
              than  the  one used for the logical_switch. Since VIP is in a different subnet, you should connect
              your logical switch to either a OVN logical router or a real router (this is  because  the  client
              can  now  send  a  packet  with  VIP as the destination IP address and router’s mac address as the
              destination MAC address).

       protocol: optional string, one of sctp, tcp, or udp
              Valid protocols are tcp, udp, or sctp. This column is useful when a port  number  is  provided  as
              part  of  the  vips  column. If this column is empty and a port number is provided as part of vips
              column, OVN assumes the protocol to be tcp.

     Health Checks:

       OVN supports health checks for load balancer endpoints. When health checks are enabled, the load balancer
       uses only healthy endpoints.

       Suppose  that  vips  contains a key-value pair 10.0.0.10:80=10.0.0.4:8080,20.0.0.4:8080. To enable health
       checks for this virtual’s endpoints, add two key-value pairs to ip_port_mappings, with keys 10.0.0.4  and
       20.0.0.4,  and  add  to  health_check a reference to a Load_Balancer_Health_Check row whose vip is set to
       10.0.0.10. The same approach can be used for IPv6 as well.

       health_check: set of Load_Balancer_Health_Checks
              Load balancer health checks associated with this load balancer.

       ip_port_mappings: map of string-string pairs
              Maps from endpoint IP to a  colon-separated  pair  of  logical  port  name  and  source  IP,  e.g.
              port_name:sourc_ip for IPv4. Health checks are sent to this port with the specified source IP. For
              IPv6 square brackets must be used around IP address, e.g: port_name:[sourc_ip]

              For  example,  in   the   example   above,   IP   to   port   mappings   might   be   defined   as
              10.0.0.4=sw0-p1:10.0.0.2 and 20.0.0.4=sw1-p1:20.0.0.2, if the values given were suitable ports and
              IP addresses.

              For IPv6 IP to port mappings might be defined as [2001::1]=sw0-p1:[2002::1].

       selection_fields: set of strings, one of eth_dst, eth_src, ip_dst, ip_src, tp_dst, or tp_src
              OVN native load balancers are supported using the OpenFlow groups of type select. OVS supports two
              selection methods: dp_hash and hash (with optional fields specified) in selecting the buckets of a
              group. Please see the OVS documentation (man ovs-ofctl) for more details on the selection methods.
              Each endpoint IP (and port if set) is mapped to a bucket in the group flow.

              CMS  can  choose  the  hash  selection  method  by  setting  the  selection fields in this column.
              ovs-vswitchd uses the specified fields in generating the hash.

              dp_hash selection method uses the assistance of datapath to calculate the hash and it is  expected
              to  be  faster than hash selection method. So CMS should take this into consideration before using
              the hash method. Please consult the OVS documentation  and  OVS  sources  for  the  implementation
              details.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

     Load_Balancer options:

       options : reject: optional string, either true or false
              If  the  load  balancer is created with --reject option and it has no active backends, a TCP reset
              segment (for tcp) or an ICMP port unreachable packet (for all other kind of traffic) will be  sent
              whenever  an incoming packet is received for this load-balancer. Please note using --reject option
              will disable empty_lb SB controller event for this load balancer.

       options : hairpin_snat_ip: optional string
              IP to be used as source IP for packets that  have  been  hair-pinned  after  load  balancing.  The
              default  behavior  when  the  option is not set is to use the load balancer VIP as source IP. This
              option may have exactly one IPv4 and/or one IPv6 address on it, separated by a space character.

       options : skip_snat: optional string
              If the load balancing rule is  configured  with  skip_snat  option,  the  option  lb_force_snat_ip
              configured  for the logical router that references this load balancer will not be applied for this
              load balancer.

       options : add_route: optional string
              If set to true, then neighbor routers will have logical flows added that will allow for routing to
              the VIP IP. It also will have ARP resolution logical flows added. By setting this option, it means
              there is no reason to create a Logical_Router_Static_Route  from  neighbor  routers  to  this  NAT
              address.  It  also  means that no ARP request is required for neighbor routers to learn the IP-MAC
              mapping for this VIP IP. For more information about what flows are added for IP routes, please see
              the ovn-northd manpage section on IP Routing.

       options : neighbor_responder: optional string
              If  set to all, then routers on which the load balancer is applied reply to ARP/neighbor discovery
              requests for all VIPs of the load balancer. If set to reachable, then routers on  which  the  load
              balancer  is  applied  reply  to  ARP/neighbor discovery requests only for VIPs that are part of a
              router’s subnet. If set to none, then routers on which the load balancer is applied never reply to
              ARP/neighbor  discovery  requests  for  any  of  the  load  balancer  VIPs.  Load  balancers  with
              options:template=true do not support reachable as a valid mode. The default value of this  option,
              if not specified, is reachable for regular load balancers and none for template load balancers.

       options : template: optional string
              Option  to be set to true, if the load balancer is a template. The load balancer VIPs and backends
              must be using Chassis_Template_Var in their definitions.

              Load balancer template VIP supported formats are:

              ^VIP_VAR[:^PORT_VAR|:port]

              where VIP_VAR and PORT_VAR are keys of the Chassis_Template_Var variables records.

              Note: The VIP and PORT cannot be  combined  into  a  single  template  variable.  For  example,  a
              Chassis_Template_Var variable expanding to 10.0.0.1:8080 is not valid if used as VIP.

              Load balancer template backend supported formats are:

              ^BACKEND_VAR1[:^PORT_VAR1|:port],^BACKEND_VAR2[:^PORT_VAR2|:port]
              or
              ^BACKENDS_VAR1,^BACKENDS_VAR2

              where  BACKEND_VAR1,  PORT_VAR1, BACKEND_VAR2, PORT_VAR2, BACKENDS_VAR1 and BACKENDS_VAR2 are keys
              of the Chassis_Template_Var variables records.

       options : address-family: optional string
              Address family used by the load balancer. Supported values are ipv4 and ipv6.  The  address-family
              is  only  used for load balancers with options:template=true. For explicit load balancers, setting
              the address-family has no effect.

       options : affinity_timeout: optional string
              If the CMS provides a positive value (in seconds) for affinity_timeout, OVN will dnat  connections
              received from the same client to this lb to the same backend if received in the affinity timeslot.
              Max supported affinity_timeout is 65535 seconds.

       options : ct_flush: optional string, either true or false
              The value indicates whether ovn-controller should flush CT entries that are related  to  this  LB.
              The  flush  happens  if the LB is removed, any of the backends is updated/removed or the LB is not
              considered local anymore by the ovn-controller. This option is set to false by default.

Load_Balancer_Group TABLE

       Each row represents a logical grouping of load balancers. It is up to the CMS to decide the  criteria  on
       which  load balancers are grouped together. To simplify configuration and to optimize its processing load
       balancers that must be associated to the same set of logical switches and/or logical  routers  should  be
       grouped together.

   Summary:
       name                          string (must be unique within table)
       load_balancer                 set of weak reference to Load_Balancers

   Details:
       name: string (must be unique within table)
              A  name  for  the  load  balancer group. This name has no special meaning or purpose other than to
              provide convenience for human interaction with the ovn-nb database.

       load_balancer: set of weak reference to Load_Balancers
              A set of load balancers.

Load_Balancer_Health_Check TABLE

       Each row represents one load balancer health check.

   Summary:
       vip                           string
       Health check options:
         options : interval          optional string, containing an integer
         options : timeout           optional string, containing an integer
         options : success_count     optional string, containing an integer
         options : failure_count     optional string, containing an integer
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       vip: string
              vip whose endpoints should be monitored for health check.

     Health check options:

       options : interval: optional string, containing an integer
              The interval, in seconds, between health checks.

       options : timeout: optional string, containing an integer
              The time, in seconds, after which a health check times out.

       options : success_count: optional string, containing an integer
              The number of successful checks after which the endpoint is considered online.

       options : failure_count: optional string, containing an integer
              The number of failure checks after which the endpoint is considered offline.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

ACL TABLE

       Each row in this table represents one ACL rule for a logical switch or a port group  that  points  to  it
       through its acls column. The action column for the highest-priority matching row in this table determines
       a packet’s treatment. If no row matches, packets are  allowed  by  default.  (Default-deny  treatment  is
       possible: add a rule with priority 0, 1 as match, and deny as action.)

   Summary:
       label                         integer, in range 0 to 4,294,967,295
       priority                      integer, in range 0 to 32,767
       direction                     string, either from-lport or to-lport
       match                         string
       action                        string, one of allow-related, allow-stateless, allow, drop, pass, or reject
       tier                          integer, in range 0 to 3
       options:
         options : apply-after-lb    optional string
       Logging:
         log                         boolean
         name                        optional string, at most 63 characters long
         severity                    optional string, one of alert, debug, info, notice, or warning
         meter                       optional string
       Common Columns:
         options                     map of string-string pairs
         ACL configuration options:
            options : log-related    optional string
         external_ids                map of string-string pairs

   Details:
       label: integer, in range 0 to 4,294,967,295
              Associates  an identifier with the ACL. The same value will be written to corresponding connection
              tracker entry. The value should be a valid  32-bit  unsigned  integer.  This  value  can  help  in
              debugging  from connection tracker side. For example, through this "label" we can backtrack to the
              ACL rule which is causing a "leaked" connection. Connection tracker entries are created  only  for
              allowed connections so the label is valid only for allow and allow-related actions.

       priority: integer, in range 0 to 32,767
              The  ACL  rule’s  priority. Rules with numerically higher priority take precedence over those with
              lower. If two ACL rules with the same priority both match, then the  one  actually  applied  to  a
              packet is undefined.

              Return traffic from an allow-related flow is always allowed and cannot be changed through an ACL.

              allow-stateless  flows  always take precedence before stateful ACLs, regardless of their priority.
              (Both allow and allow-related ACLs can be stateful.)

       direction: string, either from-lport or to-lport
              Direction of the traffic to which this rule should apply:

              •      from-lport: Used to implement filters on traffic arriving from a logical port. These  rules
                     are applied to the logical switch’s ingress pipeline.

              •      to-lport: Used to implement filters on traffic forwarded to a logical port. These rules are
                     applied to the logical switch’s egress pipeline.

       match: string
              The packets that the ACL should match, in the same expression language used for the  match  column
              in the OVN Southbound database’s Logical_Flow table. The outport logical port is only available in
              the to-lport direction (the inport is available in both directions).

              By default all traffic is allowed. When writing a more restrictive  policy,  it  is  important  to
              remember to allow flows such as ARP and IPv6 neighbor discovery packets.

              Note that you can not create an ACL matching on a port with type=router or type=localnet.

       action: string, one of allow-related, allow-stateless, allow, drop, pass, or reject
              The action to take when the ACL rule matches:

              •      allow-stateless:  Always  forward  the  packet  in  stateless  manner,  omitting connection
                     tracking mechanism, regardless of other rules defined for the switch. May require  defining
                     additional  rules  for inbound replies. For example, if you define a rule to allow outgoing
                     TCP traffic directed to an IP address, then you probably also want to define  another  rule
                     to  allow  incoming TCP traffic coming from this same IP address. In addition, traffic that
                     matches stateless ACLs will bypass load-balancer  DNAT/un-DNAT  processing.  Stateful  ACLs
                     should be used instead if the traffic is supposed to be load-balanced.

              •      allow:  Forward  the packet. It will also send the packets through connection tracking when
                     allow-related  rules  exist  on  the  logical  switch.  Otherwise,   it’s   equivalent   to
                     allow-stateless.

              •      allow-related:  Forward the packet and related traffic (e.g. inbound replies to an outbound
                     connection).

              •      drop: Silently drop the packet.

              •      reject: Drop the packet, replying with a RST for TCP or ICMPv4/ICMPv6  unreachable  message
                     for other IPv4/IPv6-based protocols.

              •      pass: Pass to the next ACL tier. If using multiple ACL tiers, a match on this ACL will stop
                     evaluating ACLs at the current tier and move to the next one. If not using ACL tiers or  if
                     a  pass ACL is matched at the final tier, then the options:default_acl_drop option from the
                     NB_Global table is used to determine how to proceed.

       tier: integer, in range 0 to 3
              The hierarchical tier that this ACL belongs to.

              ACLs can be assigned to numerical tiers. When evaluating ACLs, an  internal  counter  is  used  to
              determine  which  tier of ACLs should be evaluated. Tier 0 ACLs are evaluated first. If no verdict
              can be determined, then tier 1 ACLs are evaluated next. This  continues  until  the  maximum  tier
              value  is  reached.  If  all  tiers  of  ACLs  are  evaluated  and no verdict is reached, then the
              options:default_acl_drop option from table NB_Global is used to determine how to proceed.

              In this version of OVN, the maximum tier value for ACLs is 3, meaning there are 4  tiers  of  ACLs
              allowed (0-3).

     options:

       ACLs options.

       options : apply-after-lb: optional string
              If  set to true, the ACL will be applied after load balancing stage. Supported only for from-lport
              direction.

              The main use case of this option is to support ACLs matching on the destination IP address of  the
              packet for the backend IPs of load balancers.

              OVN  will  apply  the  from-lport ACLs in two stages. ACLs without this option apply-after-lb set,
              will be applied before the load balancer stage and ACLs with this option set will be applied after
              the load balancer stage. The priorities are indepedent between these stages and may not be obvious
              to the CMS. Hence CMS should be extra careful when using this option and should carefully evaluate
              the priorities of all the ACLs and the default deny/allow ACLs if any.

     Logging:

       These columns control whether and how OVN logs packets that match an ACL.

       log: boolean
              If  set  to  true,  packets that match the ACL will trigger a log message on the transport node or
              nodes that perform ACL processing. Logging may be combined with any action.

              If set to false, the remaining columns in this group have no significance.

       name: optional string, at most 63 characters long
              This name, if it is provided, is included in log records. It provides the  administrator  and  the
              cloud management system a way to associate a log record with a particular ACL.

       severity: optional string, one of alert, debug, info, notice, or warning
              The  severity  of  the  ACL.  The  severity  levels  match those of syslog, in decreasing level of
              severity: alert, warning, notice, info, or debug. When the column is empty, the default is info.

       meter: optional string
              The name of a meter to rate-limit log messages for the ACL. The string must match the name  column
              of  a  row  in  the Meter table. By default, log messages are not rate-limited. In order to ensure
              that the same Meter rate limits multiple ACL logs separately, set the fair column.

     Common Columns:

       options: map of string-string pairs
              This column provides general key/value settings. The supported options are described  individually
              below.

     ACL configuration options:

       options : log-related: optional string
              If  set  to true, then log when reply or related traffic is admitted from a stateful ACL. In order
              for this option to function, the log option must be set to true and a label must be  set,  and  it
              must  be  unique to the ACL. The label is necessary as it is the only means to associate the reply
              traffic with the ACL to which it belongs. It must be unique, because  otherwise  it  is  ambiguous
              which ACL will be matched. Note: If this option is enabled, an extra flow is installed in order to
              log the related traffic. Therefore, if this is enabled on all ACLs, then the total number of flows
              necessary to log the ACL traffic is doubled, compared to if this option is not enabled.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Logical_Router TABLE

       Each row represents one L3 logical router.

   Summary:
       ports                         set of Logical_Router_Ports
       static_routes                 set of Logical_Router_Static_Routes
       policies                      set of Logical_Router_Policys
       enabled                       optional boolean
       nat                           set of NATs
       load_balancer                 set of weak reference to Load_Balancers
       load_balancer_group           set of Load_Balancer_Groups
       Naming:
         name                        string
         external_ids : neutron:router_name
                                     optional string
       copp                          optional weak reference to Copp
       Options:
         options : chassis           optional string
         options : dnat_force_snat_ip
                                     optional string
         options : lb_force_snat_ip  optional string
         options : mcast_relay       optional string, either true or false
         options : dynamic_neigh_routers
                                     optional string, either true or false
         options : always_learn_from_arp_request
                                     optional string, either true or false
         options : requested-tnl-key
                                     optional string, containing an integer, in range 1 to 16,777,215
         options : snat-ct-zone      optional string, containing an integer, in range 0 to 65,535
         options : mac_binding_age_threshold
                                     optional string
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       ports: set of Logical_Router_Ports
              The router’s ports.

       static_routes: set of Logical_Router_Static_Routes
              Zero or more static routes for the router.

       policies: set of Logical_Router_Policys
              Zero or more routing policies for the router.

       enabled: optional boolean
              This  column  is  used  to administratively set router state. If this column is empty or is set to
              true, the router is enabled. If this column is set to false, the router is  disabled.  A  disabled
              router has all ingress and egress traffic dropped.

       nat: set of NATs
              One  or  more NAT rules for the router. NAT rules only work on Gateway routers, and on distributed
              routers with one and only one distributed gateway port.

       load_balancer: set of weak reference to Load_Balancers
              Set of load balancers associated to this logical router. Load balancer Load  balancer  rules  only
              work on the Gateway routers or routers with one and only one distributed gateway port.

       load_balancer_group: set of Load_Balancer_Groups
              Set of load balancers groups associated to this logical router.

     Naming:

       These  columns  provide names for the logical router. From OVN’s perspective, these names have no special
       meaning or purpose other than to provide convenience for human interaction with the northbound  database.
       There is no requirement for the name to be unique. (For a unique identifier for a logical router, use its
       row UUID.)

       (Originally, name was intended to serve the purpose of a human-friendly name, but the Neutron integration
       used it to uniquely identify its own router object, in the format neutron-uuid. Later on, Neutron started
       propagating the friendly name of a  router  as  external_ids:neutron:router_name.  Perhaps  this  can  be
       cleaned up someday.)

       name: string
              A name for the logical router.

       external_ids : neutron:router_name: optional string
              Another name for the logical router.

       copp: optional weak reference to Copp
              The  control  plane  protection  policy  from  table  Copp  used  for  metering  packets  sent  to
              ovn-controller from logical ports of this router.

     Options:

       Additional options for the logical router.

       options : chassis: optional string
              If set, indicates that the logical router in question is a Gateway router (which  is  centralized)
              and resides in the set chassis. The same value is also used by ovn-controller to uniquely identify
              the chassis in the OVN deployment and comes from external_ids:system-id in the Open_vSwitch  table
              of Open_vSwitch database.

              The Gateway router can only be connected to a distributed router via a switch if SNAT and DNAT are
              to be configured in the Gateway router.

       options : dnat_force_snat_ip: optional string
              If set, indicates a set of IP addresses to use to force SNAT a packet that has already been DNATed
              in  the  gateway  router.  When  multiple gateway routers are configured, a packet can potentially
              enter any of the gateway router, get DNATted and eventually reach the logical switch port. For the
              return  traffic  to go back to the same gateway router (for unDNATing), the packet needs a SNAT in
              the first place. This can be achieved by setting the above option with a gateway specific  set  of
              IP  addresses. This option may have exactly one IPv4 and/or one IPv6 address on it, separated by a
              a space.

       options : lb_force_snat_ip: optional string
              If set, this option can take two possible type of values. Either a set  of  IP  addresses  or  the
              string value - router_ip.

              If  a  set  of  IP  addresses  are configured, it indicates to use to force SNAT a packet that has
              already been load-balanced in the gateway router. When multiple gateway routers are configured,  a
              packet can potentially enter any of the gateway routers, get DNATted as part of the load-balancing
              and eventually reach the logical switch port. For the return  traffic  to  go  back  to  the  same
              gateway  router  (for unDNATing), the packet needs a SNAT in the first place. This can be achieved
              by setting the above option with a gateway specific set of IP  addresses.  This  option  may  have
              exactly one IPv4 and/or one IPv6 address on it, separated by a space character.

              If  it is configured with the value router_ip, then the load balanced packet is SNATed with the IP
              of router port (attached to the gateway router) selected  as  the  destination  after  taking  the
              routing decision.

       options : mcast_relay: optional string, either true or false
              Enables/disables  IP  multicast  relay  between  logical switches connected to the logical router.
              Default: False.

       options : dynamic_neigh_routers: optional string, either true or false
              If set to true, the router will resolve neighbor routers’ MAC addresses only  by  dynamic  ARP/ND,
              instead  of prepopulating static mappings for all neighbor routers in the ARP/ND Resolution stage.
              This reduces number of flows, but requires ARP/ND messages to resolve  the  IP-MAC  bindings  when
              needed.  It  is  false by default. It is recommended to set to true when a large number of logical
              routers are connected to the same logical switch but most of  them  never  need  to  send  traffic
              between  each  other.  By  default,  ovn-northd  does not create mappings to NAT and load balancer
              addresess. However, for NAT and load balancer addresses that have the add_route option added, ovn-
              northd  will  create  logical flows that map NAT and load balancer IP addresses to the appropriate
              MAC address. Setting dynamic_neigh_routers to true will prevent the automatic  creation  of  these
              logical flows.

       options : always_learn_from_arp_request: optional string, either true or false
              This  option controls the behavior when handling IPv4 ARP requests or IPv6 ND-NS packets - whether
              a dynamic neighbor (MAC binding) entry is added/updated.

              true - Always learn the MAC-IP binding, and add/update the MAC binding entry.

              false - If there is a MAC binding for that IP and the MAC is different, or, if TPA of ARP  request
              belongs  to  any router port on this router, then update/add that MAC-IP binding. Otherwise, don’t
              update/add entries.

              It is true by default. It is recommended to set to false when a large number  of  logical  routers
              are  connected to the same logical switch but most of them never need to send traffic between each
              other, to reduce the size of the MAC binding table.

       options : requested-tnl-key: optional string, containing an integer, in range 1 to 16,777,215
              Configures the datapath tunnel key for the logical router. This is not needed  because  ovn-northd
              will  assign  an  unique key for each datapath by itself. However, if it is configured, ovn-northd
              honors the configured value.

       options : snat-ct-zone: optional string, containing an integer, in range 0 to 65,535
              Use the requested conntrack zone for SNAT with this router. This can be useful if  egress  traffic
              from  the  host  running  OVN  comes  from both OVN and other sources. This way, OVN and the other
              sources can make use of the same conntrack zone.

       options : mac_binding_age_threshold: optional string
              Specifies the MAC binding aging thresholds based on CIDRs, with  the  format:  entry[;entry[...]],
              where each entry has the format: [cidr:]thresholdcidr: Can be either an IPv4 or IPv6 CIDR.

              •      threshold:  Threshold  value  in  seconds.  MAC  bindings  with  IP  addresses matching the
                     specified CIDR that exceed this timeout will be automatically removed.

              If an entry is provided without an CIDR (just the  threshold  value),  it  specifies  the  default
              threshold  for MAC bindings that don’t match any of the given CIDRs. If there are multiple default
              threshold entries in the option, the behavior is undefined.

              If there are multiple CIDRs matching a MAC binding IP, the one  with  the  longest  prefix  length
              takes  effect.  If  there  are  multiple entries with the same CIDR in the option, the behavior is
              undefined.

              If no matching CIDR is found for a MAC binding IP, and no  default  threshold  is  specified,  the
              behavior defaults to the original: the binding will not be removed based on age.

              The  value  can also default to an empty string, which means that the aging threshold is disabled.
              Any string not in the above format is regarded as invalid and the aging is disabled.

              Example: 192.168.0.0/16:300;192.168.10.0/24:0;fe80::/10:600;1200

              This sets a threshold of 300 seconds for MAC bindings with  IP  addresses  in  the  192.168.0.0/16
              range,  excluding  the  192.168.1.0/24 range (for which the aging is disabled), a threshold of 600
              seconds for MAC bindings with IP addresses in the fe80::/10 IPv6 range, and a default threshold of
              1200 seconds for all other MAC bindings.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

QoS TABLE

       Each  row  in  this  table  represents  one  QoS  rule for a logical switch that points to it through its
       qos_rules column. Two types of QoS are supported: DSCP marking and metering. A match  with  the  highest-
       priority  will have QoS applied to it. If the action column is specified, then matching packets will have
       DSCP marking applied. If the bandwidth column is specified, then  matching  packets  will  have  metering
       applied. action and bandwidth are not exclusive, so both marking and metering by defined for the same QoS
       entry. If no row matches, packets will not have any QoS applied.

   Summary:
       priority                      integer, in range 0 to 32,767
       direction                     string, either from-lport or to-lport
       match                         string
       action                        map of string-integer pairs, key either dscp or mark, value in range  0  to
                                     4,294,967,295
       bandwidth                     map  of string-integer pairs, key either burst or rate, value in range 1 to
                                     4,294,967,295
       external_ids                  map of string-string pairs

   Details:
       priority: integer, in range 0 to 32,767
              The QoS rule’s priority. Rules with numerically higher priority take precedence  over  those  with
              lower.  If  two  QoS  rules  with the same priority both match, then the one actually applied to a
              packet is undefined.

       direction: string, either from-lport or to-lport
              The value of this field is similar to ACL column in the OVN Northbound database’s ACL table.

       match: string
              The packets that the QoS rules should match, in the same expression language used  for  the  match
              column  in  the  OVN  Southbound  database’s  Logical_Flow table. The outport logical port is only
              available in the to-lport direction (the inport is available in both directions).

       action: map of string-integer pairs, key either dscp or mark, value in range 0 to 4,294,967,295
              When dscp action is specified, matching flows will have  have  DSCP  marking  applied.  When  mark
              action is specified, matching flows will have packet marking applied.

              •      dscp: The value of this action should be in the range of 0 to 63 (inclusive).

              •      mark: The value of this action should be a positive integer.

       bandwidth: map of string-integer pairs, key either burst or rate, value in range 1 to 4,294,967,295
              When specified, matching packets will have bandwidth metering applied. Traffic over the limit will
              be dropped.

              •      rate: The value of rate limit in kbps.

              •      burst: The value of burst rate limit in kilobits. This is optional and needs to specify the
                     rate.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Mirror TABLE

       Each  row  in  this  table  represents  a  mirror  that can be used for port mirroring. These mirrors are
       referenced by the mirror_rules column in the Logical_Switch_Port table.

   Summary:
       name                          string (must be unique within table)
       filter                        string, one of both, from-lport, or to-lport
       sink                          string
       type                          string, one of erspan, gre, or local
       index                         integer
       external_ids                  map of string-string pairs

   Details:
       name: string (must be unique within table)
              Represents the name of the mirror.

       filter: string, one of both, from-lport, or to-lport
              The value of this field represents selection criteria of the mirror. to-lport mirrors the  packets
              coming  into  logical port. from-lport mirrors the packets going out of logical port. both mirrors
              for both directions.

       sink: string
              The value of this field represents the destination/sink of the mirror.  If  the  type  is  gre  or
              erspan,  the value indicates the tunnel remote IP (either IPv4 or IPv6). For a type of local, this
              field defines a local  interface  on  the  OVS  integration  bridge  to  be  used  as  the  mirror
              destination. The interface must possess external-ids:mirror-id that matches this string.

       type: string, one of erspan, gre, or local
              The value of this field specifies the mirror type - gre, erspan or local.

       index: integer
              The value of this field represents the tunnel ID. If the configured tunnel type is gre, this field
              represents the GRE key value and if the  configured  tunnel  type  is  erspan  it  represents  the
              erspan_idx value. It is ignored if the type is local.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Meter TABLE

       Each row in this table represents a meter that can be used for QoS or rate-limiting.

   Summary:
       name                          string (must be unique within table)
       unit                          string, either kbps or pktps
       bands                         set of 1 or more Meter_Bands
       fair                          optional boolean
       external_ids                  map of string-string pairs

   Details:
       name: string (must be unique within table)
              A name for this meter.

              Names  that  begin with "__" (two underscores) are reserved for OVN internal use and should not be
              added manually.

       unit: string, either kbps or pktps
              The unit for rate and burst_rate parameters in  the  bands  entry.  kbps  specifies  kilobits  per
              second, and pktps specifies packets per second.

       bands: set of 1 or more Meter_Bands
              The  bands  associated with this meter. Each band specifies a rate above which the band is to take
              the action action. If multiple bands’ rates are exceeded, then the  band  with  the  highest  rate
              among the exceeded bands is selected.

       fair: optional boolean
              This  column is used to further describe the desired behavior of the meter when there are multiple
              references to it. If this column is empty or is set to false, the rate will be shared  across  all
              rows  that refer to the same Meter name. Conversely, when this column is set to true, each user of
              the same Meter will be rate-limited on its own.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Meter_Band TABLE

       Each row in this table represents a meter band which specifies the rate above which the configured action
       should be applied. These bands are referenced by the bands column in the Meter table.

   Summary:
       action                        string, must be drop
       rate                          integer, in range 1 to 4,294,967,295
       burst_size                    integer, in range 0 to 4,294,967,295
       external_ids                  map of string-string pairs

   Details:
       action: string, must be drop
              The action to execute when this band matches. The only supported action is drop.

       rate: integer, in range 1 to 4,294,967,295
              The  rate limit for this band, in kilobits per second or bits per second, depending on whether the
              parent Meter entry’s unit column specified kbps or pktps.

       burst_size: integer, in range 0 to 4,294,967,295
              The maximum burst allowed for the band in kilobits or packets, depending on whether kbps or  pktps
              was  selected  in the parent Meter entry’s unit column. If the size is zero, the switch is free to
              select some reasonable value depending on its configuration.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Logical_Router_Port TABLE

       A port within an L3 logical router.

       Exactly one Logical_Router row must reference a given logical router port.

   Summary:
       name                          string (must be unique within table)
       networks                      set of 1 or more strings
       mac                           string
       enabled                       optional boolean
       Distributed Gateway Ports:
         ha_chassis_group            optional HA_Chassis_Group
         gateway_chassis             set of Gateway_Chassises
         Options for Physical VLAN MTU Issues:
            options : reside-on-redirect-chassis
                                     optional string, either true or false
            options : redirect-type  optional string, either bridged or overlay
       ipv6_prefix                   set of strings
       ipv6_ra_configs:
         ipv6_ra_configs : address_mode
                                     optional string
         ipv6_ra_configs : router_preference
                                     optional string
         ipv6_ra_configs : route_info
                                     optional string
         ipv6_ra_configs : mtu       optional string
         ipv6_ra_configs : send_periodic
                                     optional string
         ipv6_ra_configs : max_interval
                                     optional string
         ipv6_ra_configs : min_interval
                                     optional string
         ipv6_ra_configs : rdnss     optional string
         ipv6_ra_configs : dnssl     optional string
       Options:
         options : mcast_flood       optional string, either true or false
         options : requested-tnl-key
                                     optional string, containing an integer, in range 1 to 32,767
         options : prefix_delegation
                                     optional string, either true or false
         options : prefix            optional string, either true or false
         options : route_table       optional string
         options : gateway_mtu       optional string, containing an integer, in range 68 to 65,535
         options : gateway_mtu_bypass
                                     optional string
       Attachment:
         peer                        optional string
       Common Columns:
         external_ids                map of string-string pairs
       Status:
         status : hosting-chassis    optional string

   Details:
       name: string (must be unique within table)
              A name for the logical router port.

              In addition to provide convenience for human interaction with the northbound database, this column
              is  used  as  reference by its patch port in Logical_Switch_Port or another logical router port in
              Logical_Router_Port.

              A logical router port may not have the same name as a logical switch port, but the database schema
              cannot enforce this.

       networks: set of 1 or more strings
              The  IP  addresses  and  netmasks  of  the  router. For example, 192.168.0.1/24 indicates that the
              router’s IP address is 192.168.0.1 and that packets destined to 192.168.0.x should  be  routed  to
              this port.

              A  logical  router  port always adds a link-local IPv6 address (fe80::/64) automatically generated
              from the interface’s MAC address using the modified EUI-64 format.

       mac: string
              The Ethernet address that belongs to this router port.

       enabled: optional boolean
              This column is used to administratively set port state. If this column is empty or is set to true,
              the port is enabled. If this column is set to false, the port is disabled. A disabled port has all
              ingress and egress traffic dropped.

     Distributed Gateway Ports:

       Gateways, as documented under Gateways in  the  OVN  architecture  guide,  provide  limited  connectivity
       between   logical   networks   and   physical   ones.   OVN  support  multiple  kinds  of  gateways.  The
       Logical_Router_Port table can be used two different ways to configure distributed  gateway  ports,  which
       are  one  kind  of  gateway.  These two forms of configuration exist for historical reasons. Both of them
       produce the same kind of OVN southbound records and the same behavior in practice.

       If either of these are set, this logical router port represents a distributed gateway port that  connects
       this router to a logical switch with a localnet port or a connection to another OVN deployment.

       Also  mentioned in the OVN architecture guide, distributed gateway ports can also be used for scalability
       reasons in deployments where logical switches are dedicated to chassises rather than distributed.

       The preferred way to configure a gateway is ha_chassis_group, but gateway_chassis is also  supported  for
       backward  compatibility.  Only  one of these should be set at a time on a given LRP, since they configure
       the same features.

       Even when a gateway is configured, the logical router port still effectively  resides  on  each  chassis.
       However,  due  to the implications of the use of L2 learning in the physical network, as well as the need
       to support advanced features such as one-to-many NAT (aka IP  masquerading),  a  subset  of  the  logical
       router processing is handled in a centralized manner on the gateway chassis.

       There  can  be more than one distributed gateway ports configured on each logical router, each connecting
       to different L2 segments. Load-balancing is not yet supported on  logical  routers  with  more  than  one
       distributed gateway ports.

       For  each  distributed  gateway  port,  it  may  have more than one gateway chassises. When more than one
       gateway chassis is specified, OVN only uses one at a time. OVN can rely  on  OVS  BFD  implementation  to
       monitor  gateway  connectivity,  preferring  the  highest-priority gateway that is online. Priorities are
       specified in the priority column of Gateway_Chassis or HA_Chassis.

       ovn-northd programs the external_mac rules specified in the LRP’s  LR  into  the  peer  logical  switch’s
       destination  lookup  on the chassis where the logical_port resides. In addition, the logical router’s MAC
       address is automatically programmed in the peer logical switch’s destination lookup flow on  the  gateway
       chasssis.  If  it  is  desired  to  generate  gratuitous  ARPs for NAT addresses, then set the peer LSP’s
       options:nat-addresses to router.

       OVN  20.03  and  earlier  supported  a  third  way  to  configure   distributed   gateway   ports   using
       options:redirect-chassis  to  specify  the  gateway  chassis.  This  method  is  no longer supported. Any
       remaining users should switch to one of the newer  methods  instead.  A  gateway_chassis  may  be  easily
       configured from the command line, e.g. ovn-nbctl lrp-set-gateway-chassis lrp chassis.

       ha_chassis_group: optional HA_Chassis_Group
              Designates an HA_Chassis_Group to provide gateway high availability.

       gateway_chassis: set of Gateway_Chassises
              Designates one or more Gateway_Chassis for the logical router port.

     Options for Physical VLAN MTU Issues:

       MTU  issues  arise  in  mixing  tunnels with logical networks that are bridged to a physical VLAN. For an
       explanation of the MTU issues, see Physical VLAN  MTU  Issues  in  the  OVN  architecture  document.  The
       following  options, which are alternatives, provide solutions. Both of them cause packets to be sent over
       localnet instead of tunnels, but they differ in whether some or all packets are sent this way.  The  most
       prominent  tradeoff  between  these options is that reside-on-redirect-chassis is easier to configure and
       that redirect-type performs better for east-west traffic.

       options : reside-on-redirect-chassis: optional string, either true or false
              If set to true, this option forces all traffic across the logical router port to pass through  the
              gateway chassis using a hop across a localnet port. This changes behavior in two ways:

              •      Without  this  option,  east-west  traffic  passes  directly between source and destination
                     chassis (or even within a single chassis, for co-located VMs). With this option, all  east-
                     west traffic passes through the gateway chassis.

              •      Without  this option, traffic between the gateway chassis and other chassis is encapsulated
                     in tunnels. With this option, traffic passes over a localnet interface.

              This option may usefully be set only on logical router ports that connect  a  distributed  logical
              router to a logical switch with VIFs. It should not be set on a distributed gateway port.

              OVN  honors  this  option only if the logical router has one and only one distributed gateway port
              and if the LRP’s peer switch has a localnet port.

       options : redirect-type: optional string, either bridged or overlay
              If set to bridged on a distributed gateway port, this option causes OVN to redirect packets to the
              gateway  chassis  over  a  localnet  port  instead  of a tunnel. The relevant chassis must share a
              localnet port.

              This feature requires the administrator or the CMS to configure each participating chassis with  a
              unique  Ethernet  address  for  the logical router by setting ovn-chassis-mac-mappings in the Open
              vSwitch database, for use by ovn-controller.

              Setting this option to overlay or leaving it unset has no effect. This option may usefully be  set
              only  on a distributed gateway port when there is one and only one distributed gateway port on the
              logical router. It is otherwise ignored.

       ipv6_prefix: set of strings
              This column contains IPv6 prefix obtained by prefix delegation router according to RFC 3633

     ipv6_ra_configs:

       This column defines the IPv6 ND RA address mode and ND MTU Option to be included by  ovn-controller  when
       it replies to the IPv6 Router solicitation requests.

       ipv6_ra_configs : address_mode: optional string
              The address mode to be used for IPv6 address configuration. The supported values are:

              •      slaac:  Address  configuration  using  Router  Advertisement (RA) packet. The IPv6 prefixes
                     defined in the Logical_Router_Port table’s networks column will be  included  in  the  RA’s
                     ICMPv6 option - Prefix information.

              •      dhcpv6_stateful: Address configuration using DHCPv6.

              •      dhcpv6_stateless:  Address configuration using Router Advertisement (RA) packet. Other IPv6
                     options are provided by DHCPv6.

       ipv6_ra_configs : router_preference: optional string
              Default Router Preference (PRF) indicates whether to prefer this router over other default routers
              (RFC 4191). Possible values are:

              •      HIGH: mapped to 0x01 in RA PRF field

              •      MEDIUM: mapped to 0x00 in RA PRF field

              •      LOW: mapped to 0x11 in RA PRF field

       ipv6_ra_configs : route_info: optional string
              Route  Info  is  used to configure Route Info Option sent in Router Advertisement according to RFC
              4191. Route Info is a comma separated string where each field provides PRF and prefix for a  given
              route (e.g: HIGH-aef1::11/48,LOW-aef2::11/96) Possible PRF values are:

              •      HIGH: mapped to 0x01 in RA PRF field

              •      MEDIUM: mapped to 0x00 in RA PRF field

              •      LOW: mapped to 0x11 in RA PRF field

       ipv6_ra_configs : mtu: optional string
              The  recommended  MTU for the link. Default is 0, which means no MTU Option will be included in RA
              packet replied by ovn-controller. Per RFC 2460, the mtu value is recommended no less than 1280, so
              any mtu value less than 1280 will be considered as no MTU Option.

       ipv6_ra_configs : send_periodic: optional string
              If  set  to  true,  then  this  router interface will send router advertisements periodically. The
              default is false.

       ipv6_ra_configs : max_interval: optional string
              The maximum number of seconds to wait between sending periodic router advertisements. This  option
              has no effect if ipv6_ra_configs:send_periodic is false. The default is 600.

       ipv6_ra_configs : min_interval: optional string
              The  minimum number of seconds to wait between sending periodic router advertisements. This option
              has  no  effect  if  ipv6_ra_configs:send_periodic  is  false.  The  default   is   one-third   of
              ipv6_ra_configs:max_interval, i.e. 200 seconds if that key is unset.

       ipv6_ra_configs : rdnss: optional string
              IPv6  address  of  RDNSS server announced in RA packets. At the moment OVN supports just one RDNSS
              server.

       ipv6_ra_configs : dnssl: optional string
              DNS Search List announced in RA packets. Multiple DNS Search List must be ’comma’ separated  (e.g.
              "a.b.c, d.e.f")

     Options:

       Additional options for the logical router port.

       options : mcast_flood: optional string, either true or false
              If  set  to  true,  multicast  traffic  (including  reports)  are unconditionally forwarded to the
              specific port.

              This option applies when the port is part of a logical router which has options:mcast_relay set to
              true.

              Default: false.

       options : requested-tnl-key: optional string, containing an integer, in range 1 to 32,767
              Configures the port binding tunnel key for the port. Usually this is not needed because ovn-northd
              will assign an unique key for each port by itself. However, if it is configured, ovn-northd honors
              the configured value.

       options : prefix_delegation: optional string, either true or false
              If set to true, enable IPv6 prefix delegation state machine on this logical router port (RFC3633).
              IPv6 prefix delegation is available just on a gateway router or on a gateway router port.

       options : prefix: optional string, either true or false
              If set to true, this interface will receive an IPv6 prefix according to RFC3663

       options : route_table: optional string
              Designates  lookup  Logical_Router_Static_Routes  with  specified  route_table  value.  Routes  to
              directly  connected  networks  from  same Logical Router and routes without route_table option set
              have higher priority than routes with route_table option set.

       options : gateway_mtu: optional string, containing an integer, in range 68 to 65,535
              If set, logical flows will be added to router pipeline to check packet length. If packet length is
              greater  than  the value set, ICMPv4 type 3 (Destination Unreachable) code 4 (Fragmentation Needed
              and Don’t Fragment was Set) or ICMPv6 type 2 (Packet Too Big) code 0  (no  route  to  destination)
              packets will be generated. This allows for Path MTU Discovery.

       options : gateway_mtu_bypass: optional string
              When configured, represents a match expression, in the same expression language used for the match
              column in the OVN Southbound database’s Logical_Flow table. Packets matching this expression  will
              bypass the length check configured through the options:gateway_mtu option.

     Attachment:

       A given router port serves one of two purposes:

              •      To  attach  a  logical  switch  to  a logical router. A logical router port of this type is
                     referenced by exactly one Logical_Switch_Port of type router. The value of name is  set  as
                     router-port in column options of Logical_Switch_Port. In this case peer column is empty.

              •      To  connect  one  logical  router to another. This requires a pair of logical router ports,
                     each connected to a different router. Each router port in the pair specifies the  other  in
                     its peer column. No Logical_Switch refers to the router port.

       peer: optional string
              For  a  router  port used to connect two logical routers, this identifies the other router port in
              the pair by name.

              For a router port attached to a logical switch, this column is empty.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

              The ovn-northd program copies all these pairs into the external_ids  column  of  the  Port_Binding
              table in OVN_Southbound database.

     Status:

       Additional status about the logical router port.

       status : hosting-chassis: optional string
              This option is populated by ovn-northd.

              When a distributed gateway port is bound to a location in the OVN Southbound database Port_Binding
              ovn-northd will populate this key with the name of the Chassis  that  is  currently  hosting  this
              port.

Logical_Router_Static_Route TABLE

       Each record represents a static route.

       When  multiple  routes  match  a packet, the longest-prefix match is chosen. For a given prefix length, a
       dst-ip route is preferred over a src-ip route.

       When there are ECMP routes, i.e. multiple routes with same  prefix  and  policy,  one  of  them  will  be
       selected based on the 5-tuple hashing of the packet header.

   Summary:
       ip_prefix                     string
       policy                        optional string, either dst-ip or src-ip
       nexthop                       string
       output_port                   optional string
       bfd                           optional weak reference to BFD
       route_table                   string
       external_ids : ic-learned-route
                                     optional string
       Common Columns:
         external_ids                map of string-string pairs
       Common options:
         options                     map of string-string pairs
         options : ecmp_symmetric_reply
                                     optional string
         options : origin            optional string

   Details:
       ip_prefix: string
              IP prefix of this route (e.g. 192.168.100.0/24).

       policy: optional string, either dst-ip or src-ip
              If it is specified, this setting describes the policy used to make routing decisions. This setting
              must be one of the following strings:

              •      src-ip: This policy sends the packet to the nexthop when the  packet’s  source  IP  address
                     matches ip_prefix.

              •      dst-ip:  This  policy  sends  the  packet  to  the nexthop when the packet’s destination IP
                     address matches ip_prefix.

              If not specified, the default is dst-ip.

       nexthop: string
              Nexthop IP address for this route. Nexthop IP address should be the  IP  address  of  a  connected
              router  port  or  the  IP  address of a logical port or can be set to discard for dropping packets
              which match the given route.

       output_port: optional string
              The name of the Logical_Router_Port via which the packet needs to be sent out.  This  is  optional
              and  when not specified, OVN will automatically figure this out based on the nexthop. When this is
              specified and there are multiple IP addresses on the router port and none of them are in the  same
              subnet of nexthop, OVN chooses the first IP address as the one via which the nexthop is reachable.

       bfd: optional weak reference to BFD
              Reference to BFD row if the route has associated a BFD session

       route_table: string
              Any  string  to place route to separate routing table. If Logical Router Port has configured value
              in options:route_table other than empty string, OVN performs route lookup for all packets entering
              Logical Router ingress pipeline from this port in the following manner:

              •      1.  First  lookup among "global" routes: routes without route_table value set and routes to
                     directly connected networks.

              •      2.  Next  lookup  among  routes  with  same  route_table  value  as  specified   in   LRP’s
                     options:route_table field.

       external_ids : ic-learned-route: optional string
              ovn-ic  populates  this key if the route is learned from the global OVN_IC_Southbound database. In
              this case the value will be set to the uuid of the row in Route  table  of  the  OVN_IC_Southbound
              database.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

     Common options:

       options: map of string-string pairs
              This  column provides general key/value settings. The supported options are described individually
              below.

       options : ecmp_symmetric_reply: optional string
              If true, then new traffic that arrives over this route will have its  reply  traffic  bypass  ECMP
              route selection and will be sent out this route instead. Note that this option overrides any rules
              set in the Logical_Router_policy table. This option only works on gateway  routers  (routers  that
              have options:chassis set).

       options : origin: optional string
              In  case  ovn-interconnection  has  been  learned  this route, it will have its origin set: either
              "connected" or "static". This key is supposed to be written only by ovn-ic daemon. ovn-northd then
              checks  this  value  when  generating Logical Flows. Logical_Router_Static_Route records with same
              ip_prefix within same Logical Router will have next lookup order based on origin key value:

              1.  connected

              2.  static

Logical_Router_Policy TABLE

       Each row in this table represents one routing policy for a logical router that points to it  through  its
       policies  column.  The  action  column  for  the highest-priority matching row in this table determines a
       packet’s treatment. If no row matches,  packets  are  allowed  by  default.  (Default-deny  treatment  is
       possible: add a rule with priority 0, 1 as match, and drop as action.)

   Summary:
       priority                      integer, in range 0 to 32,767
       match                         string
       action                        string, one of allow, drop, or reroute
       nexthop                       optional string
       nexthops                      set of strings
       bfd_sessions                  set of weak reference to BFDs
       options : pkt_mark            optional string
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       priority: integer, in range 0 to 32,767
              The  routing  policy’s priority. Rules with numerically higher priority take precedence over those
              with lower. A rule is uniquely identified by the priority and match string.

       match: string
              The packets that the routing policy should match, in the same expression  language  used  for  the
              match column in the OVN Southbound database’s Logical_Flow table.

              By  default  all  traffic  is  allowed. When writing a more restrictive policy, it is important to
              remember to allow flows such as ARP and IPv6 neighbor discovery packets.

       action: string, one of allow, drop, or reroute
              The action to take when the routing policy matches:

              •      allow: Forward the packet.

              •      drop: Silently drop the packet.

              •      reroute: Reroute packet to nexthop or nexthops.

       nexthop: optional string
              Note: This column is deprecated in favor of nexthops.

              Next-hop IP address for this route, which should be the IP address of a connected router  port  or
              the IP address of a logical port.

       nexthops: set of strings
              Next-hop  ECMP  IP  addresses  for  this  route. Each IP in the list should be the IP address of a
              connected router port or the IP address of a logical port.

              One IP from the list is selected as next hop.

       bfd_sessions: set of weak reference to BFDs
              Reference to BFD row if the route policy has associated some BFD sessions.

       options : pkt_mark: optional string
              Marks the packet with the value specified when the router policy is applied. CMS can inspect  this
              packet marker and take some decisions if desired. This value is not preserved when the packet goes
              out on the wire.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

NAT TABLE

       Each record represents a NAT rule.

   Summary:
       type                          string, one of dnat, dnat_and_snat, or snat
       external_ip                   string
       external_mac                  optional string
       external_port_range           string
       logical_ip                    string
       logical_port                  optional string
       allowed_ext_ips               optional Address_Set
       exempted_ext_ips              optional Address_Set
       gateway_port                  optional weak reference to Logical_Router_Port
       options : stateless           optional string
       options : add_route           optional string
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       type: string, one of dnat, dnat_and_snat, or snat
              Type of the NAT rule.

              •      When type is dnat, the externally visible IP address  external_ip  is  DNATted  to  the  IP
                     address logical_ip in the logical space.

              •      When  type  is  snat,  IP  packets  with their source IP address that either matches the IP
                     address in logical_ip or is in the network provided by logical_ip is  SNATed  into  the  IP
                     address in external_ip.

              •      When type is dnat_and_snat, the externally visible IP address external_ip is DNATted to the
                     IP address logical_ip in the logical space. In addition, IP  packets  with  the  source  IP
                     address that matches logical_ip is SNATed into the IP address in external_ip.

       external_ip: string
              An IPv4 address.

       external_mac: optional string
              A MAC address.

              This  is only used on the gateway port on distributed routers. This must be specified in order for
              the NAT rule to be processed in a distributed manner on all chassis. If this is not specified  for
              a  NAT  rule on a distributed router, then this NAT rule will be processed in a centralized manner
              on the gateway port instance on the gateway chassis.

              This MAC address must be unique on the logical switch that the gateway port is attached to. If the
              MAC address used on the logical_port is globally unique, then that MAC address can be specified as
              this external_mac.

       external_port_range: string
              L4 source port range

              Range of ports, from which a port number will be picked that will replace the source port of to be
              NATed packet. This is basically PAT (port address translation).

              Value  of  the  column  is  in  the  format,  port_lo-port_hi.  For example: external_port_range :
              "1-30000"

              Valid range of ports is 1-65535.

       logical_ip: string
              An IPv4 network (e.g 192.168.1.0/24) or an IPv4 address.

       logical_port: optional string
              The name of the logical port where the logical_ip resides.

              This is only used on distributed routers. This must be specified in order for the NAT rule  to  be
              processed  in  a  distributed  manner on all chassis. If this is not specified for a NAT rule on a
              distributed router, then this NAT rule will be processed in a centralized manner  on  the  gateway
              port instance on the gateway chassis.

       allowed_ext_ips: optional Address_Set
              It represents Address Set of external ips that NAT rule is applicable to. For SNAT type NAT rules,
              this refers to destination addresses. For DNAT type NAT rules, this refers to source addresses.

              This configuration overrides the default NAT behavior of applying a rule solely based on  internal
              IP.  Without  this configuration, NAT happens without considering the external IP (i.e dest/source
              for snat/dnat type rule). With this configuration NAT rule is applied ONLY if external  ip  is  in
              the input Address Set.

       exempted_ext_ips: optional Address_Set
              It  represents  Address  Set of external ips that NAT rule is NOT applicable to. For SNAT type NAT
              rules, this refers to destination addresses. For DNAT  type  NAT  rules,  this  refers  to  source
              addresses.

              This  configuration overrides the default NAT behavior of applying a rule solely based on internal
              IP. Without this configuration, NAT happens without considering the external IP  (i.e  dest/source
              for snat/dnat type rule). With this configuration NAT rule is NOT applied if external ip is in the
              input Address Set.

              If there are NAT rules in a logical router with overlapping  IP  prefixes  (including  /32),  then
              usage of exempted_ext_ips should be avoided in following scenario. a. SNAT rule (let us say RULE1)
              with logical_ip PREFIX/MASK (let us say 50.0.0.0/24).  b.  SNAT  rule  (let  us  say  RULE2)  with
              logical_ip  PREFIX/MASK+1 (let us say 50.0.0.0/25). c. Now, if exempted_ext_ips is associated with
              RULE2, then a logical ip which matches both 50.0.0.0/24 and 50.0.0.0/25 may get the RULE2  applied
              to it instead of RULE1.

              allowed_ext_ips  and  exempted_ext_ips  are mutually exclusive to each other. If both Address Sets
              are set for a rule, then the NAT rule is not considered.

       gateway_port: optional weak reference to Logical_Router_Port
              A distributed gateway port in the Logical_Router_Port  table  where  the  NAT  rule  needs  to  be
              applied.

              When multiple distributed gateway ports are configured on a Logical_Router, applying a NAT rule at
              each of the distributed gateway ports might not be desired. Consider  the  case  where  a  logical
              router  has 2 distributed gateway port, one with networks 50.0.0.10/24 and the other with networks
              60.0.0.10/24. If the logical router has a NAT  rule  of  type  snat,  logical_ip  10.1.1.0/24  and
              external_ip   50.1.1.20/24,  the  rule  needs  to  be  selectively  applied  on  matching  packets
              entering/leaving through the distributed gateway port with networks 50.0.0.10/24.

              When a logical router has multiple distributed gateway ports and this column is not set for a  NAT
              rule,  then  the rule will be applied at the distributed gateway port which is in the same network
              as the external_ip of the NAT rule, if such a router port exists. If logical router has  a  single
              distributed  gateway  port  and this column is not set for a NAT rule, the rule will be applied at
              the distributed gateway port even if the router port is not in the same network as the external_ip
              of the NAT rule.

       options : stateless: optional string
              Indicates if a dnat_and_snat rule should lead to connection tracking state or not.

       options : add_route: optional string
              If set to true, then neighbor routers will have logical flows added that will allow for routing to
              the NAT address. It also will have ARP resolution logical flows added. By setting this option,  it
              means there is no reason to create a Logical_Router_Static_Route from neighbor routers to this NAT
              address. It also means that no ARP request is required for neighbor routers to  learn  the  IP-MAC
              mapping for this NAT address. This option only applies to NATs of type dnat and dnat_and_snat. For
              more information about what flows are added for IP  routes,  please  see  the  ovn-northd  manpage
              section on IP Routing.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

DHCP_Options TABLE

       OVN  implements native DHCPv4 support which caters to the common use case of providing an IPv4 address to
       a booting instance by providing stateless replies to  DHCPv4  requests  based  on  statically  configured
       address  mappings.  To  do  this it allows a short list of DHCPv4 options to be configured and applied at
       each compute host running ovn-controller.

       OVN also implements native DHCPv6 support which provides stateless replies to DHCPv6 requests.

   Summary:
       cidr                          string
       DHCPv4 options:
         Mandatory DHCPv4 options:
            options : server_id      optional string
            options : server_mac     optional string
            options : lease_time     optional string, containing an integer, in range 0 to 4,294,967,295
         IPv4 DHCP Options:
            options : router         optional string
            options : netmask        optional string
            options : dns_server     optional string
            options : log_server     optional string
            options : lpr_server     optional string
            options : swap_server    optional string
            options : policy_filter  optional string
            options : router_solicitation
                                     optional string
            options : nis_server     optional string
            options : ntp_server     optional string
            options : netbios_name_server
                                     optional string
            options : classless_static_route
                                     optional string
            options : ms_classless_static_route
                                     optional string
            options : next_server    optional string
         Boolean DHCP Options:
            options : ip_forward_enable
                                     optional string, either 0 or 1
            options : router_discovery
                                     optional string, either 0 or 1
            options : ethernet_encap optional string, either 0 or 1
         Integer DHCP Options:
            options : default_ttl    optional string, containing an integer, in range 0 to 255
            options : tcp_ttl        optional string, containing an integer, in range 0 to 255
            options : mtu            optional string, containing an integer, in range 68 to 65,535
            options : T1             optional string, containing an integer, in range 68 to 4,294,967,295
            options : T2             optional string, containing an integer, in range 68 to 4,294,967,295
            options : arp_cache_timeout
                                     optional string, containing an integer, in range 0 to 255
            options : tcp_keepalive_interval
                                     optional string, containing an integer, in range 0 to 255
            options : netbios_node_type
                                     optional string, containing an integer, in range 0 to 255
         String DHCP Options:
            options : wpad           optional string
            options : bootfile_name  optional string
            options : path_prefix    optional string
            options : tftp_server_address
                                     optional string
            options : hostname       optional string
            options : domain_name    optional string
            options : bootfile_name_alt
                                     optional string
            options : broadcast_address
                                     optional string
         DHCP Options of type host_id:
            options : tftp_server    optional string
          DHCP Options of type domains:
            options : domain_search_list
                                     optional string
       DHCPv6 options:
         Mandatory DHCPv6 options:
            options : server_id      optional string
         IPv6 DHCPv6 options:
            options : dns_server     optional string
         String DHCPv6 options:
            options : domain_search  optional string
            options : dhcpv6_stateless
                                     optional string
            options : fqdn           optional string
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       cidr: string
              The DHCPv4/DHCPv6 options will be included if the logical port has its IP address in this cidr.

     DHCPv4 options:

       The CMS should define the set of DHCPv4 options as key/value pairs in the options column of  this  table.
       For  ovn-controller  to  include  these  DHCPv4 options, the dhcpv4_options of Logical_Switch_Port should
       refer to an entry in this table.

     Mandatory DHCPv4 options:

       The following options must be defined.

       options : server_id: optional string
              The IP address for the DHCP server to use. This should be in the subnet of the offered IP. This is
              also included in the DHCP offer as option 54, ``server identifier.’’

       options : server_mac: optional string
              The Ethernet address for the DHCP server to use.

       options : lease_time: optional string, containing an integer, in range 0 to 4,294,967,295
              The offered lease time in seconds,

              The DHCPv4 option code for this option is 51.

     IPv4 DHCP Options:

       Below  are  the supported DHCPv4 options whose values are an IPv4 address, e.g. 192.168.1.1. Some options
       accept multiple IPv4 addresses enclosed within curly  braces,  e.g.  {192.168.1.2,  192.168.1.3}.  Please
       refer to RFC 2132 for more details on DHCPv4 options and their codes.

       options : router: optional string
              The IP address of a gateway for the client to use. This should be in the subnet of the offered IP.
              The DHCPv4 option code for this option is 3.

       options : netmask: optional string
              The DHCPv4 option code for this option is 1.

       options : dns_server: optional string
              The DHCPv4 option code for this option is 6.

       options : log_server: optional string
              The DHCPv4 option code for this option is 7.

       options : lpr_server: optional string
              The DHCPv4 option code for this option is 9.

       options : swap_server: optional string
              The DHCPv4 option code for this option is 16.

       options : policy_filter: optional string
              The DHCPv4 option code for this option is 21.

       options : router_solicitation: optional string
              The DHCPv4 option code for this option is 32.

       options : nis_server: optional string
              The DHCPv4 option code for this option is 41.

       options : ntp_server: optional string
              The DHCPv4 option code for this option is 42.

       options : netbios_name_server: optional string
              The DHCPv4 option code for this option is 44.

       options : classless_static_route: optional string
              The DHCPv4 option code for this option is 121.

              This option can contain one or more static  routes,  each  of  which  consists  of  a  destination
              descriptor  and the IP address of the router that should be used to reach that destination. Please
              see RFC 3442 for more details.

              Example: {30.0.0.0/24,10.0.0.10, 0.0.0.0/0,10.0.0.1}

       options : ms_classless_static_route: optional string
              The DHCPv4 option code for this option is 249. This option is  similar  to  classless_static_route
              supported by Microsoft Windows DHCPv4 clients.

       options : next_server: optional string
              The DHCPv4 option code for setting the "Next server IP address" field in the DHCP header.

     Boolean DHCP Options:

       These options accept a Boolean value, expressed as 0 for false or 1 for true.

       options : ip_forward_enable: optional string, either 0 or 1
              The DHCPv4 option code for this option is 19.

       options : router_discovery: optional string, either 0 or 1
              The DHCPv4 option code for this option is 31.

       options : ethernet_encap: optional string, either 0 or 1
              The DHCPv4 option code for this option is 36.

     Integer DHCP Options:

       These options accept a nonnegative integer value.

       options : default_ttl: optional string, containing an integer, in range 0 to 255
              The DHCPv4 option code for this option is 23.

       options : tcp_ttl: optional string, containing an integer, in range 0 to 255
              The DHCPv4 option code for this option is 37.

       options : mtu: optional string, containing an integer, in range 68 to 65,535
              The DHCPv4 option code for this option is 26.

       options : T1: optional string, containing an integer, in range 68 to 4,294,967,295
              This  specifies  the time interval from address assignment until the client begins trying to renew
              its address. The DHCPv4 option code for this option is 58.

       options : T2: optional string, containing an integer, in range 68 to 4,294,967,295
              This specifies the time interval from address assignment until the client begins trying to  rebind
              its address. The DHCPv4 option code for this option is 59.

       options : arp_cache_timeout: optional string, containing an integer, in range 0 to 255
              The DHCPv4 option code for this option is 35. This option specifies the timeout in seconds for ARP
              cache entries.

       options : tcp_keepalive_interval: optional string, containing an integer, in range 0 to 255
              The DHCPv4 option code for this option is 38. This option specifies the interval that  the  client
              TCP should wait before sending a keepalive message on a TCP connection.

       options : netbios_node_type: optional string, containing an integer, in range 0 to 255
              The DHCPv4 option code for this option is 46.

     String DHCP Options:

       These options accept a string value.

       options : wpad: optional string
              The  DHCPv4  option  code  for  this  option is 252. This option is used as part of web proxy auto
              discovery to provide a URL for a web proxy.

       options : bootfile_name: optional string
              The DHCPv4 option code for this option is 67. This option is used to identify a bootfile.

       options : path_prefix: optional string
              The DHCPv4 option code for this option is 210. In PXELINUX’ case this option  is  used  to  set  a
              common path prefix, instead of deriving it from the bootfile name.

       options : tftp_server_address: optional string
              The DHCPv4 option code for this option is 150. The option contains one or more IPv4 addresses that
              the client MAY use. This option is Cisco proprietary, the IEEE standard  that  matches  with  this
              requirement is option 66 (tftp_server).

       options : hostname: optional string
              The  DHCPv4  option  code  for  this option is 12. If set, indicates the DHCPv4 option "Hostname".
              Alternatively,  this  option   can   be   configured   in   options:hostname   column   in   table
              Logical_Switch_Port.  If  Hostname option value is set in both conflicting Logical_Switch_Port and
              DHCP_Options tables, Logical_Switch_Port takes precedence.

       options : domain_name: optional string
              The DHCPv4 option code for this option is 15. This option specifies the domain  name  that  client
              should use when resolving hostnames via the Domain Name System.

       options : bootfile_name_alt: optional string
              "bootfile_name_alt"   option   is   used   to   support   iPXE.   When  both  "bootfile_name"  and
              "bootfile_name_alt" are provided by the CMS, "bootfile_name" will be used for  option  67  if  the
              dhcp request contains etherboot option (175), otherwise "bootfile_name_alt" will be used.

       options : broadcast_address: optional string
              The  DHCPv4  option  code  for  this  option is 28. This option specifies the IP address used as a
              broadcast address.

     DHCP Options of type host_id:

       These options accept either an IPv4 address or a string value.

       options : tftp_server: optional string
              The DHCPv4 option code for this option is 66.

      DHCP Options of type domains:

       These options accept string value which is a comma separated list of domain names. The domain  names  are
       encoded based on RFC 1035.

       options : domain_search_list: optional string
              The DHCPv4 option code for this option is 119.

     DHCPv6 options:

       OVN  also  implements native DHCPv6 support. The CMS should define the set of DHCPv6 options as key/value
       pairs.  The  define  DHCPv6  options  will  be  included  in  the   DHCPv6   response   to   the   DHCPv6
       Solicit/Request/Confirm packet from the logical ports having the IPv6 addresses in the cidr.

     Mandatory DHCPv6 options:

       The following options must be defined.

       options : server_id: optional string
              The  Ethernet  address  for  the  DHCP server to use. This is also included in the DHCPv6 reply as
              option 2, ``Server Identifier’’ to carry a DUID identifying  a  server  between  a  client  and  a
              server. ovn-controller defines DUID based on Link-layer Address [DUID-LL].

     IPv6 DHCPv6 options:

       Below  are  the  supported  DHCPv6  options  whose values are an IPv6 address, e.g. aef0::4. Some options
       accept multiple IPv6 addresses enclosed within curly braces, e.g. {aef0::4, aef0::5}. Please refer to RFC
       3315 for more details on DHCPv6 options and their codes.

       options : dns_server: optional string
              The  DHCPv6  option  code for this option is 23. This option specifies the DNS servers that the VM
              should use.

     String DHCPv6 options:

       These options accept string values.

       options : domain_search: optional string
              The DHCPv6 option code for this option is 24. This option specifies the  domain  search  list  the
              client should use to resolve hostnames with DNS.

              Example: "ovn.org".

       options : dhcpv6_stateless: optional string
              This  option  specifies  the OVN native DHCPv6 will work in stateless mode, which means OVN native
              DHCPv6 will not offer IPv6 addresses for VM/VIF ports, but only reply other  configurations,  such
              as  DNS  and  domain  search  list. When setting this option with string value "true", VM/VIF will
              configure IPv6 addresses by stateless way. Default value for this option is false.

       options : fqdn: optional string
              The DHCPv6 option code for this option is 39. If set, indicates the DHCPv6 option "FQDN".

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

Connection TABLE

       Configuration for a database connection to an Open vSwitch database (OVSDB) client.

       This table primarily configures the Open vSwitch database server (ovsdb-server).

       The Open vSwitch database server can initiate and maintain active connections to remote clients.  It  can
       also listen for database connections.

   Summary:
       Core Features:
         target                      string (must be unique within table)
       Client Failure Detection and Handling:
         max_backoff                 optional integer, at least 1,000
         inactivity_probe            optional integer
       Status:
         is_connected                boolean
         status : last_error         optional string
         status : state              optional string, one of ACTIVE, BACKOFF, CONNECTING, IDLE, or VOID
         status : sec_since_connect  optional string, containing an integer, at least 0
         status : sec_since_disconnect
                                     optional string, containing an integer, at least 0
         status : locks_held         optional string
         status : locks_waiting      optional string
         status : locks_lost         optional string
         status : n_connections      optional string, containing an integer, at least 2
         status : bound_port         optional string, containing an integer
       Common Columns:
         external_ids                map of string-string pairs
         other_config                map of string-string pairs

   Details:
     Core Features:

       target: string (must be unique within table)
              Connection methods for clients.

              The following connection methods are currently supported:

              ssl:host[:port]
                     The  specified  SSL  port on the host at the given host, which can either be a DNS name (if
                     built with unbound library) or an IP address. A valid SSL configuration  must  be  provided
                     when this form is used, this configuration can be specified via command-line options or the
                     SSL table.

                     If port is not specified, it defaults to 6640.

                     SSL support is an optional feature that is not always built as part of Open vSwitch.

              tcp:host[:port]
                     The specified TCP port on the host at the given host, which can either be a  DNS  name  (if
                     built with unbound library) or an IP address. If host is an IPv6 address, wrap it in square
                     brackets, e.g. tcp:[::1]:6640.

                     If port is not specified, it defaults to 6640.

              pssl:[port][:host]
                     Listens for SSL connections on the specified TCP port. Specify  0  for  port  to  have  the
                     kernel  automatically choose an available port. If host, which can either be a DNS name (if
                     built with unbound library) or an IP address, is specified, then connections are restricted
                     to  the  resolved or specified local IPaddress (either IPv4 or IPv6 address). If host is an
                     IPv6 address, wrap in square brackets, e.g. pssl:6640:[::1]. If host is not specified  then
                     it  listens  only  on  IPv4  (but  not  IPv6)  addresses. A valid SSL configuration must be
                     provided when this form is used, this can be specified either via command-line  options  or
                     the SSL table.

                     If port is not specified, it defaults to 6640.

                     SSL support is an optional feature that is not always built as part of Open vSwitch.

              ptcp:[port][:host]
                     Listens  for  connections  on the specified TCP port. Specify 0 for port to have the kernel
                     automatically choose an available port. If host, which can either be a DNS name  (if  built
                     with  unbound  library)  or an IP address, is specified, then connections are restricted to
                     the resolved or specified local IP address (either IPv4 or IPv6 address).  If  host  is  an
                     IPv6  address,  wrap  it in square brackets, e.g. ptcp:6640:[::1]. If host is not specified
                     then it listens only on IPv4 addresses.

                     If port is not specified, it defaults to 6640.

              When multiple clients are configured, the target values must be unique.  Duplicate  target  values
              yield unspecified results.

     Client Failure Detection and Handling:

       max_backoff: optional integer, at least 1,000
              Maximum  number  of  milliseconds  to wait between connection attempts. Default is implementation-
              specific.

       inactivity_probe: optional integer
              Maximum number of milliseconds of idle  time  on  connection  to  the  client  before  sending  an
              inactivity  probe  message. If Open vSwitch does not communicate with the client for the specified
              number of seconds, it will send a probe. If a response is not received  for  the  same  additional
              amount  of  time,  Open  vSwitch assumes the connection has been broken and attempts to reconnect.
              Default is implementation-specific. A value of 0 disables inactivity probes.

     Status:

       Key-value pair of is_connected is always updated. Other key-value pairs in  the  status  columns  may  be
       updated depends on the target type.

       When  target  specifies  a connection method that listens for inbound connections (e.g. ptcp: or punix:),
       both n_connections and is_connected may also be updated while the remaining key-value pairs are omitted.

       On the other hand, when target specifies an outbound connection, all  key-value  pairs  may  be  updated,
       except  the  above-mentioned  two  key-value  pairs  associated with inbound connection targets. They are
       omitted.

       is_connected: boolean
              true if currently connected to this client, false otherwise.

       status : last_error: optional string
              A  human-readable  description  of  the  last  error  on  the  connection  to  the  manager;  i.e.
              strerror(errno). This key will exist only if an error has occurred.

       status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING, IDLE, or VOID
              The state of the connection to the manager:

              VOID   Connection is disabled.

              BACKOFF
                     Attempting to reconnect at an increasing period.

              CONNECTING
                     Attempting to connect.

              ACTIVE Connected, remote host responsive.

              IDLE   Connection is idle. Waiting for response to keep-alive.

              These values may change in the future. They are provided only for human consumption.

       status : sec_since_connect: optional string, containing an integer, at least 0
              The  amount  of  time  since this client last successfully connected to the database (in seconds).
              Value is empty if client has never successfully been connected.

       status : sec_since_disconnect: optional string, containing an integer, at least 0
              The amount of time since this client last disconnected from the database (in  seconds).  Value  is
              empty if client has never disconnected.

       status : locks_held: optional string
              Space-separated  list  of  the  names  of  OVSDB  locks  that the connection holds. Omitted if the
              connection does not hold any locks.

       status : locks_waiting: optional string
              Space-separated list of the names of OVSDB locks that  the  connection  is  currently  waiting  to
              acquire. Omitted if the connection is not waiting for any locks.

       status : locks_lost: optional string
              Space-separated  list  of  the  names of OVSDB locks that the connection has had stolen by another
              OVSDB client. Omitted if no locks have been stolen from this connection.

       status : n_connections: optional string, containing an integer, at least 2
              When target specifies a connection method that listens for  inbound  connections  (e.g.  ptcp:  or
              pssl:)  and  more  than  one  connection  is  actually  active,  the value is the number of active
              connections. Otherwise, this key-value pair is omitted.

       status : bound_port: optional string, containing an integer
              When target is ptcp: or pssl:, this is the TCP port on which the OVSDB server is listening.  (This
              is  particularly  useful  when  target  specifies  a  port of 0, allowing the kernel to choose any
              available port.)

     Common Columns:

       The overall purpose of these columns is described under Common Columns at the beginning of this document.

       external_ids: map of string-string pairs

       other_config: map of string-string pairs

DNS TABLE

       Each row in this table stores the DNS records. The Logical_Switch table’s  dns_records  references  these
       records.

   Summary:
       records                       map of string-string pairs
       options : ovn-owned           optional string
       external_ids                  map of string-string pairs

   Details:
       records: map of string-string pairs
              Key-value  pair  of  DNS  records  with  DNS  query  name  as  the key and value as a string of IP
              address(es) separated by comma or space. For PTR requests, the key-value pair can be Reverse  IPv4
              address.in-addr.arpa  and the value DNS domain name. For IPv6 addresses, the key has to be Reverse
              IPv6 address.ip6.arpa.

              Example:  "vm1.ovn.org" = "10.0.0.4 aef0::4"

              Example:  "4.0.0.10.in-addr.arpa" = "vm1.ovn.org"

       options : ovn-owned: optional string
              If set to true, then the OVN will be the main responsible for DNS Records within this row.

              A DNS row with this option set to true can be created for domains that the user needs to configure
              locally  and  don’t  care about IPv6 only interested in IPv4 or vice versa. This will let ovn send
              IPv4 DNS reply and reject/ignore IPv6  queries  to  save  the  waiting  for  a  timeout  on  those
              uninteresting queries.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

SSL TABLE

       SSL configuration for ovn-nb database access.

   Summary:
       private_key                   string
       certificate                   string
       ca_cert                       string
       bootstrap_ca_cert             boolean
       ssl_protocols                 string
       ssl_ciphers                   string
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       private_key: string
              Name of a PEM file containing the private key used as the switch’s identity for SSL connections to
              the controller.

       certificate: string
              Name of a PEM file containing a certificate, signed by the certificate authority (CA) used by  the
              controller and manager, that certifies the switch’s private key, identifying a trustworthy switch.

       ca_cert: string
              Name  of a PEM file containing the CA certificate used to verify that the switch is connected to a
              trustworthy controller.

       bootstrap_ca_cert: boolean
              If set to true, then Open vSwitch will attempt to obtain the CA certificate from the controller on
              its  first  SSL  connection  and  save  it  to  the  named  PEM file. If it is successful, it will
              immediately drop the connection and reconnect, and from  then  on  all  SSL  connections  must  be
              authenticated by a certificate signed by the CA certificate thus obtained. This option exposes the
              SSL connection to a man-in-the-middle attack obtaining the initial CA certificate. It may still be
              useful for bootstrapping.

       ssl_protocols: string
              List  of  SSL protocols to be enabled for SSL connections. The default when this option is omitted
              is TLSv1,TLSv1.1,TLSv1.2.

       ssl_ciphers: string
              List of ciphers (in OpenSSL cipher string format) to be supported for SSL connections. The default
              when this option is omitted is HIGH:!aNULL:!MD5.

     Common Columns:

       The overall purpose of these columns is described under Common Columns at the beginning of this document.

       external_ids: map of string-string pairs

Gateway_Chassis TABLE

       Association  of a chassis to a logical router port. The traffic going out through an specific router port
       will be redirected to a chassis, or a set of them in high availability configurations.

   Summary:
       name                          string (must be unique within table)
       chassis_name                  string
       priority                      integer, in range 0 to 32,767
       options                       map of string-string pairs
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: string (must be unique within table)
              Name of the Gateway_Chassis.

              A suggested, but not required naming convention is ${port_name}_${chassis_name}.

       chassis_name: string
              Name of the chassis that we want to redirect traffic through for  the  associated  logical  router
              port. The value must match the name column of the Chassis table in the OVN_Southbound database.

       priority: integer, in range 0 to 32,767
              This  is  the priority of a chassis among all Gateway_Chassis belonging to the same logical router
              port.

       options: map of string-string pairs
              Reserved for future use.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

HA_Chassis_Group TABLE

       Table representing a group of chassis which can provide high availability services. Each chassis  in  the
       group  is represented by the table HA_Chassis. The HA chassis with highest priority will be the master of
       this group. If the master chassis failover is detected, the HA chassis  with  the  next  higher  priority
       takes  over the responsibility of providing the HA. If a distributed gateway router port references a row
       in this table, then the master HA chassis in this group provides the gateway functionality.

   Summary:
       name                          string (must be unique within table)
       ha_chassis                    set of HA_Chassises
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       name: string (must be unique within table)
              Name of the HA_Chassis_Group. Name should be unique.

       ha_chassis: set of HA_Chassises
              A list of HA chassis which belongs to this group.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

HA_Chassis TABLE

   Summary:
       chassis_name                  string
       priority                      integer, in range 0 to 32,767
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       chassis_name: string
              Name of the chassis which is part of the HA chassis group. The value must match the name column of
              the Chassis table in the OVN_Southbound database.

       priority: integer, in range 0 to 32,767
              Priority of the chassis. Chassis with highest priority will be the master.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

BFD TABLE

       Contains  BFD  parameter  for ovn-controller BFD configuration. OVN BFD implementation is used to provide
       detection of failures in the path between adjacent forwarding engines, including the OVN interfaces.  OVN
       BFD  provides  link status info to OVN northd in order to update logical flows according to the status of
       BFD endpoints. In the current implementation OVN BFD is used to check next-hop status  for  ECMP  routes.
       Please note BFD table refers to OVN BFD implementation and not to OVS legacy one.

   Summary:
       Configuration:
         logical_port                string
         dst_ip                      string
         min_tx                      optional integer, at least 1
         min_rx                      optional integer
         detect_mult                 optional integer, at least 1
         options                     map of string-string pairs
         external_ids                map of string-string pairs
       Status Reporting:
         status                      optional string, one of admin_down, down, init, or up

   Details:
     Configuration:

       ovn-northd reads configuration from these columns.

       logical_port: string
              OVN logical port when BFD engine is running.

       dst_ip: string
              BFD peer IP address.

       min_tx: optional integer, at least 1
              This  is  the  minimum  interval,  in  milliseconds,  that the local system would like to use when
              transmitting BFD Control packets, less any jitter applied. The value  zero  is  reserved.  Default
              value is 1000 ms.

       min_rx: optional integer
              This  is  the  minimum  interval,  in milliseconds, between received BFD Control packets that this
              system is capable of supporting, less any jitter applied by the sender. If this value is zero, the
              transmitting system does not want the remote system to send any periodic BFD Control packets.

       detect_mult: optional integer, at least 1
              Detection  time  multiplier.  The negotiated transmit interval, multiplied by this value, provides
              the Detection Time for the receiving system in Asynchronous mode. Default value is 5.

       options: map of string-string pairs
              Reserved for future use.

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.

     Status Reporting:

       ovn-northd writes BFD status into these columns.

       status: optional string, one of admin_down, down, init, or up
              BFD port logical states. Possible values are:

              •      admin_downdowninitup

Static_MAC_Binding TABLE

       Each record represents a Static_MAC_Binding entry for a logical router.

   Summary:
       Configuration:
         logical_port                string
         ip                          string
         mac                         string
         override_dynamic_mac        boolean

   Details:
     Configuration:

       ovn-northd reads configuration from these columns and propagates the value to SBDB.

       logical_port: string
              The logical router port for the binding.

       ip: string
              The bound IP address.

       mac: string
              The Ethernet address to which the IP is bound.

       override_dynamic_mac: boolean
              Override dynamically learnt MACs.

Chassis_Template_Var TABLE

       One record per chassis, each containing a map, variables, between template variable names and their value
       for  that  specific chassis. A template variable has a name and potentially different values on different
       hypervisors in the OVN cluster. For example, two rows, R1 = (.chassis=C1, variables={(N: V1)}  and  R2  =
       (.chassis=C2,  variables={(N:  V2)}  will  make ovn-controller running on chassis C1 and C2 interpret the
       token N either as V1 (on C1) or as V2 (on C2). Users can refer to template variables  from  within  other
       logical  components, e.g., within ACL, QoS or Logical_Router_Policy matches or from Load_Balancer VIP and
       backend definitions.

       If a template variable is  referenced  on  a  chassis  for  which  that  variable  is  not  defined  then
       ovn-controller running on that chassis will just interpret it as a raw string literal.

   Summary:
       chassis                       string (must be unique within table)
       variables                     map of string-string pairs
       Common Columns:
         external_ids                map of string-string pairs

   Details:
       chassis: string (must be unique within table)
              The chassis this set of variable values applies to.

       variables: map of string-string pairs
              The set of variable values for a given chassis.

     Common Columns:

       external_ids: map of string-string pairs
              See External IDs at the beginning of this document.