Provided by: openvswitch-switch_2.17.9-0ubuntu0.22.04.1_amd64 
NAME
ovs-vswitchd - Open vSwitch daemon
SYNOPSIS
ovs-vswitchd [database]
DESCRIPTION
A daemon that manages and controls any number of Open vSwitch switches on the local
machine.
The database argument specifies how ovs-vswitchd connects to ovsdb-server. database may
be an OVSDB active or passive connection method, as described in ovsdb(7). The default is
unix:/var/run/openvswitch/db.sock.
ovs-vswitchd retrieves its configuration from database at startup. It sets up Open
vSwitch datapaths and then operates switching across each bridge described in its
configuration files. As the database changes, ovs-vswitchd automatically updates its
configuration to match.
ovs-vswitchd switches may be configured with any of the following features:
• L2 switching with MAC learning.
• NIC bonding with automatic fail-over and source MAC-based TX load balancing
("SLB").
• 802.1Q VLAN support.
• Port mirroring, with optional VLAN tagging.
• NetFlow v5 flow logging.
• sFlow(R) monitoring.
• Connectivity to an external OpenFlow controller, such as NOX.
Only a single instance of ovs-vswitchd is intended to run at a time. A single
ovs-vswitchd can manage any number of switch instances, up to the maximum number of
supported Open vSwitch datapaths.
ovs-vswitchd does all the necessary management of Open vSwitch datapaths itself. Thus,
ovs-dpctl(8) (and its userspace datapath counterparts accessible via ovs-appctl
dpctl/command) are not needed with ovs-vswitchd and should not be used because they can
interfere with its operation. These tools are still useful for diagnostics.
An Open vSwitch datapath kernel module must be loaded for ovs-vswitchd to be useful.
Refer to the documentation for instructions on how to build and load the Open vSwitch
kernel module.
OPTIONS
--mlockall
Causes ovs-vswitchd to call the mlockall() function, to attempt to lock all of its
process memory into physical RAM, preventing the kernel from paging any of its
memory to disk. This helps to avoid networking interruptions due to system memory
pressure.
Some systems do not support mlockall() at all, and other systems only allow
privileged users, such as the superuser, to use it. ovs-vswitchd emits a log
message if mlockall() is unavailable or unsuccessful.
DPDK Options
For details on initializing ovs-vswitchd to use DPDK ports, refer to the documentation or
ovs-vswitchd.conf.db(5).
Daemon Options
The following options are valid on POSIX based platforms.
--pidfile[=pidfile]
Causes a file (by default, ovs-vswitchd.pid) to be created indicating the PID of
the running process. If the pidfile argument is not specified, or if it does not
begin with /, then it is created in /var/run/openvswitch.
If --pidfile is not specified, no pidfile is created.
--overwrite-pidfile
By default, when --pidfile is specified and the specified pidfile already exists
and is locked by a running process, ovs-vswitchd refuses to start. Specify
--overwrite-pidfile to cause it to instead overwrite the pidfile.
When --pidfile is not specified, this option has no effect.
--detach
Runs ovs-vswitchd as a background process. The process forks, and in the child it
starts a new session, closes the standard file descriptors (which has the side
effect of disabling logging to the console), and changes its current directory to
the root (unless --no-chdir is specified). After the child completes its
initialization, the parent exits. ovs-vswitchd detaches only after it has
connected to the database, retrieved the initial configuration, and set up that
configuration.
--monitor
Creates an additional process to monitor the ovs-vswitchd daemon. If the daemon
dies due to a signal that indicates a programming error (SIGABRT, SIGALRM, SIGBUS,
SIGFPE, SIGILL, SIGPIPE, SIGSEGV, SIGXCPU, or SIGXFSZ) then the monitor process
starts a new copy of it. If the daemon dies or exits for another reason, the
monitor process exits.
This option is normally used with --detach, but it also functions without it.
--no-chdir
By default, when --detach is specified, ovs-vswitchd changes its current working
directory to the root directory after it detaches. Otherwise, invoking
ovs-vswitchd from a carelessly chosen directory would prevent the administrator
from unmounting the file system that holds that directory.
Specifying --no-chdir suppresses this behavior, preventing ovs-vswitchd from
changing its current working directory. This may be useful for collecting core
files, since it is common behavior to write core dumps into the current working
directory and the root directory is not a good directory to use.
This option has no effect when --detach is not specified.
--no-self-confinement
By default daemon will try to self-confine itself to work with files under well-
known directories determined during build. It is better to stick with this default
behavior and not to use this flag unless some other Access Control is used to
confine daemon. Note that in contrast to other access control implementations that
are typically enforced from kernel-space (e.g. DAC or MAC), self-confinement is
imposed from the user-space daemon itself and hence should not be considered as a
full confinement strategy, but instead should be viewed as an additional layer of
security.
--user Causes ovs-vswitchd to run as a different user specified in "user:group", thus
dropping most of the root privileges. Short forms "user" and ":group" are also
allowed, with current user or group are assumed respectively. Only daemons started
by the root user accepts this argument.
On Linux, daemons will be granted CAP_IPC_LOCK and CAP_NET_BIND_SERVICES before
dropping root privileges. Daemons that interact with a datapath, such as
ovs-vswitchd, will be granted three additional capabilities, namely CAP_NET_ADMIN,
CAP_NET_BROADCAST and CAP_NET_RAW. The capability change will apply even if the
new user is root.
On Windows, this option is not currently supported. For security reasons,
specifying this option will cause the daemon process not to start.
Service Options
The following options are valid only on Windows platform.
--service
Causes ovs-vswitchd to run as a service in the background. The service should
already have been created through external tools like SC.exe.
--service-monitor
Causes the ovs-vswitchd service to be automatically restarted by the Windows
services manager if the service dies or exits for unexpected reasons.
When --service is not specified, this option has no effect.
Public Key Infrastructure Options
-p privkey.pem
--private-key=privkey.pem
Specifies a PEM file containing the private key used as ovs-vswitchd's identity for
outgoing SSL connections.
-c cert.pem
--certificate=cert.pem
Specifies a PEM file containing a certificate that certifies the private key
specified on -p or --private-key to be trustworthy. The certificate must be signed
by the certificate authority (CA) that the peer in SSL connections will use to
verify it.
-C cacert.pem
--ca-cert=cacert.pem
Specifies a PEM file containing the CA certificate that ovs-vswitchd should use to
verify certificates presented to it by SSL peers. (This may be the same
certificate that SSL peers use to verify the certificate specified on -c or
--certificate, or it may be a different one, depending on the PKI design in use.)
-C none
--ca-cert=none
Disables verification of certificates presented by SSL peers. This introduces a
security risk, because it means that certificates cannot be verified to be those of
known trusted hosts.
--bootstrap-ca-cert=cacert.pem
When cacert.pem exists, this option has the same effect as -C or --ca-cert. If it
does not exist, then ovs-vswitchd will attempt to obtain the CA certificate from
the SSL peer 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, but it may be useful for bootstrapping.
This option is only useful if the SSL peer sends its CA certificate as part of the
SSL certificate chain. The SSL protocol does not require the server to send the CA
certificate.
This option is mutually exclusive with -C and --ca-cert.
--peer-ca-cert=peer-cacert.pem
Specifies a PEM file that contains one or more additional certificates to send to
SSL peers. peer-cacert.pem should be the CA certificate used to sign
ovs-vswitchd's own certificate, that is, the certificate specified on -c or
--certificate. If ovs-vswitchd's certificate is self-signed, then --certificate
and --peer-ca-cert should specify the same file.
This option is not useful in normal operation, because the SSL peer must already
have the CA certificate for the peer to have any confidence in ovs-vswitchd's
identity. However, this offers a way for a new installation to bootstrap the CA
certificate on its first SSL connection.
Logging Options
-v[spec]
--verbose=[spec]
Sets logging levels. Without any spec, sets the log level for every module and
destination to dbg. Otherwise, spec is a list of words separated by spaces or
commas or colons, up to one from each category below:
• A valid module name, as displayed by the vlog/list command on ovs-appctl(8),
limits the log level change to the specified module.
• syslog, console, or file, to limit the log level change to only to the
system log, to the console, or to a file, respectively. (If --detach is
specified, ovs-vswitchd closes its standard file descriptors, so logging to
the console will have no effect.)
On Windows platform, syslog is accepted as a word and is only useful along
with the --syslog-target option (the word has no effect otherwise).
• off, emer, err, warn, info, or dbg, to control the log level. Messages of
the given severity or higher will be logged, and messages of lower severity
will be filtered out. off filters out all messages. See ovs-appctl(8) for
a definition of each log level.
Case is not significant within spec.
Regardless of the log levels set for file, logging to a file will not take place
unless --log-file is also specified (see below).
For compatibility with older versions of OVS, any is accepted as a word but has no
effect.
-v
--verbose
Sets the maximum logging verbosity level, equivalent to --verbose=dbg.
-vPATTERN:destination:pattern
--verbose=PATTERN:destination:pattern
Sets the log pattern for destination to pattern. Refer to ovs-appctl(8) for a
description of the valid syntax for pattern.
-vFACILITY:facility
--verbose=FACILITY:facility
Sets the RFC5424 facility of the log message. facility can be one of kern, user,
mail, daemon, auth, syslog, lpr, news, uucp, clock, ftp, ntp, audit, alert, clock2,
local0, local1, local2, local3, local4, local5, local6 or local7. If this option is
not specified, daemon is used as the default for the local system syslog and local0
is used while sending a message to the target provided via the --syslog-target
option.
--log-file[=file]
Enables logging to a file. If file is specified, then it is used as the exact name
for the log file. The default log file name used if file is omitted is
/var/log/openvswitch/ovs-vswitchd.log.
--syslog-target=host:port
Send syslog messages to UDP port on host, in addition to the system syslog. The
host must be a numerical IP address, not a hostname.
--syslog-method=method
Specify method how syslog messages should be sent to syslog daemon. Following
forms are supported:
• libc, use libc syslog() function. Downside of using this options is that
libc adds fixed prefix to every message before it is actually sent to the
syslog daemon over /dev/log UNIX domain socket.
• unix:file, use UNIX domain socket directly. It is possible to specify
arbitrary message format with this option. However, rsyslogd 8.9 and older
versions use hard coded parser function anyway that limits UNIX domain
socket use. If you want to use arbitrary message format with older rsyslogd
versions, then use UDP socket to localhost IP address instead.
• udp:ip:port, use UDP socket. With this method it is possible to use
arbitrary message format also with older rsyslogd. When sending syslog
messages over UDP socket extra precaution needs to be taken into account,
for example, syslog daemon needs to be configured to listen on the specified
UDP port, accidental iptables rules could be interfering with local syslog
traffic and there are some security considerations that apply to UDP
sockets, but do not apply to UNIX domain sockets.
• null, discards all messages logged to syslog.
The default is taken from the OVS_SYSLOG_METHOD environment variable; if it is
unset, the default is libc.
Other Options
--unixctl=socket
Sets the name of the control socket on which ovs-vswitchd listens for runtime
management commands (see RUNTIME MANAGEMENT COMMANDS, below). If socket does not
begin with /, it is interpreted as relative to /var/run/openvswitch. If --unixctl
is not used at all, the default socket is
/var/run/openvswitch/ovs-vswitchd.pid.ctl, where pid is ovs-vswitchd's process ID.
On Windows a local named pipe is used to listen for runtime management commands. A
file is created in the absolute path as pointed by socket or if --unixctl is not
used at all, a file is created as ovs-vswitchd.ctl in the configured OVS_RUNDIR
directory. The file exists just to mimic the behavior of a Unix domain socket.
Specifying none for socket disables the control socket feature.
-h
--help Prints a brief help message to the console.
-V
--version
Prints version information to the console.
RUNTIME MANAGEMENT COMMANDS
ovs-appctl(8) can send commands to a running ovs-vswitchd process. The currently
supported commands are described below. The command descriptions assume an understanding
of how to configure Open vSwitch.
GENERAL COMMANDS
exit --cleanup
Causes ovs-vswitchd to gracefully terminate. If --cleanup is specified, deletes
flows from datapaths and releases other datapath resources configured by
ovs-vswitchd. Otherwise, datapath flows and other resources remains undeleted.
Resources of datapaths that are integrated into ovs-vswitchd (e.g. the netdev
datapath type) are always released regardless of --cleanup except for ports with
internal type. Use --cleanup to release internal ports too.
qos/show-types interface
Queries the interface for a list of Quality of Service types that are configurable
via Open vSwitch for the given interface.
qos/show interface
Queries the kernel for Quality of Service configuration and statistics associated
with the given interface.
bfd/show [interface]
Displays detailed information about Bidirectional Forwarding Detection configured
on interface. If interface is not specified, then displays detailed information
about all interfaces with BFD enabled.
bfd/set-forwarding [interface] status
Force the fault status of the BFD module on interface (or all interfaces if none is
given) to be status. status can be "true", "false", or "normal" which reverts to
the standard behavior.
cfm/show [interface]
Displays detailed information about Connectivity Fault Management configured on
interface. If interface is not specified, then displays detailed information about
all interfaces with CFM enabled.
cfm/set-fault [interface] status
Force the fault status of the CFM module on interface (or all interfaces if none is
given) to be status. status can be "true", "false", or "normal" which reverts to
the standard behavior.
stp/tcn [bridge]
Forces a topology change event on bridge if it's running STP. This may cause it to
send Topology Change Notifications to its peers and flush its MAC table. If no
bridge is given, forces a topology change event on all bridges.
stp/show [bridge]
Displays detailed information about spanning tree on the bridge. If bridge is not
specified, then displays detailed information about all bridges with STP enabled.
rstp/tcn [bridge]
Forces a topology change event on bridge if it's running RSTP. This may cause it
to send Topology Change Notifications to its peers and flush its MAC table. If no
bridge is given, forces a topology change event on all bridges.
rstp/show [bridge]
Displays detailed information about rapid spanning tree on the bridge. If bridge
is not specified, then displays detailed information about all bridges with RSTP
enabled.
BRIDGE COMMANDS
These commands manage bridges.
fdb/add bridge port vlan mac
Adds mac address to a port and vlan on a bridge. This utility can be used to pre-
populate fdb table without relying on dynamic mac learning.
fdb/del bridge vlan mac
Deletes mac address from a port and vlan on a bridge.
fdb/flush [bridge]
Flushes bridge MAC address learning table, or all learning tables if no bridge is
given.
fdb/show bridge
Lists each MAC address/VLAN pair learned by the specified bridge, along with the
port on which it was learned and the age of the entry, in seconds.
fdb/stats-clear [bridge]
Clear bridge MAC address learning table statistics, or all statistics if no bridge
is given.
fdb/stats-show bridge
Show MAC address learning table statistics for the specified bridge.
mdb/flush [bridge]
Flushes bridge multicast snooping table, or all snooping tables if no bridge is
given.
mdb/show bridge
Lists each multicast group/VLAN pair learned by the specified bridge, along with
the port on which it was learned and the age of the entry, in seconds.
bridge/reconnect [bridge]
Makes bridge drop all of its OpenFlow controller connections and reconnect. If
bridge is not specified, then all bridges drop their controller connections and
reconnect.
This command might be useful for debugging OpenFlow controller issues.
bridge/dump-flows [--offload-stats] bridge
Lists all flows in bridge, including those normally hidden to commands such as
ovs-ofctl dump-flows. Flows set up by mechanisms such as in-band control and fail-
open are hidden from the controller since it is not allowed to modify or override
them. If --offload-stats are specified then also list statistics for offloaded
packets and bytes, which are a subset of the total packets and bytes.
BOND COMMANDS
These commands manage bonded ports on an Open vSwitch's bridges. To understand some of
these commands, it is important to understand a detail of the bonding implementation
called ``source load balancing'' (SLB). Instead of directly assigning Ethernet source
addresses to members, the bonding implementation computes a function that maps an 48-bit
Ethernet source addresses into an 8-bit value (a ``MAC hash'' value). All of the Ethernet
addresses that map to a single 8-bit value are then assigned to a single member.
bond/list
Lists all of the bonds, and their members, on each bridge.
bond/show [port]
Lists all of the bond-specific information (updelay, downdelay, time until the next
rebalance) about the given bonded port, or all bonded ports if no port is given.
Also lists information about each members: whether it is enabled or disabled, the
time to completion of an updelay or downdelay if one is in progress, whether it is
the active member, the hashes assigned to the member. Any LACP information related
to this bond may be found using the lacp/show command.
bond/migrate port hash member
Only valid for SLB bonds. Assigns a given MAC hash to a new member. port
specifies the bond port, hash the MAC hash to be migrated (as a decimal number
between 0 and 255), and member the new member to be assigned.
The reassignment is not permanent: rebalancing or fail-over will cause the MAC hash
to be shifted to a new member in the usual manner.
A MAC hash cannot be migrated to a disabled member.
bond/set-active-member port member
Sets member as the active member on port. member must currently be enabled.
The setting is not permanent: a new active member will be selected if member
becomes disabled.
bond/enable-member port member
bond/disable-member port member
Enables (or disables) member on the given bond port, skipping any updelay (or
downdelay).
This setting is not permanent: it persists only until the carrier status of member
changes.
bond/hash mac [vlan] [basis]
Returns the hash value which would be used for mac with vlan and basis if
specified.
lacp/show [port]
Lists all of the LACP related information about the given port: active or passive,
aggregation key, system id, and system priority. Also lists information about each
member: whether it is enabled or disabled, whether it is attached or detached, port
id and priority, actor information, and partner information. If port is not
specified, then displays detailed information about all interfaces with CFM
enabled.
lacp/stats-show [port]
Lists various stats about LACP PDUs (number of RX/TX PDUs, bad PDUs received) and
member state (number of times its state expired/defaulted and carrier status
changed) for the given port. If port is not specified, then displays stats of all
interfaces with LACP enabled.
DPCTL DATAPATH DEBUGGING COMMANDS
The primary way to configure ovs-vswitchd is through the Open vSwitch database, e.g. using
ovs-vsctl(8). These commands provide a debugging interface for managing datapaths. They
implement the same features (and syntax) as ovs-dpctl(8). Unlike ovs-dpctl(8), these
commands work with datapaths that are integrated into ovs-vswitchd (e.g. the netdev
datapath type).
Do not use commands to add or remove or modify datapaths if ovs-vswitchd is running
because this interferes with ovs-vswitchd's own datapath management.
dpctl/add-dp dp [netdev[,option]...]
Creates datapath dp, with a local port also named dp. This will fail if a network
device dp already exists.
If netdevs are specified, ovs-vswitchd adds them to the new datapath, just as if
add-if was specified.
dpctl/del-dp dp
Deletes datapath dp. If dp is associated with any network devices, they are
automatically removed.
dpctl/add-if dp netdev[,option]...
Adds each netdev to the set of network devices datapath dp monitors, where dp is
the name of an existing datapath, and netdev is the name of one of the host's
network devices, e.g. eth0. Once a network device has been added to a datapath,
the datapath has complete ownership of the network device's traffic and the network
device appears silent to the rest of the system.
A netdev may be followed by a comma-separated list of options. The following
options are currently supported:
type=type
Specifies the type of port to add. The default type is system.
port_no=port
Requests a specific port number within the datapath. If this option is not
specified then one will be automatically assigned.
key=value
Adds an arbitrary key-value option to the port's configuration.
ovs-vswitchd.conf.db(5) documents the available port types and options.
dpctl/set-if dp port[,option]...
Reconfigures each port in dp as specified. An option of the form key=value adds
the specified key-value option to the port or overrides an existing key's value.
An option of the form key=, that is, without a value, deletes the key-value named
key. The type and port number of a port cannot be changed, so type and port_no are
only allowed if they match the existing configuration.
dpctl/del-if dp netdev...
Removes each netdev from the list of network devices datapath dp monitors.
dpctl/dump-dps
Prints the name of each configured datapath on a separate line.
dpctl/show [-s | --statistics] [dp...]
Prints a summary of configured datapaths, including their datapath numbers and a
list of ports connected to each datapath. (The local port is identified as port
0.) If -s or --statistics is specified, then packet and byte counters are also
printed for each port.
The datapath numbers consists of flow stats and mega flow mask stats.
The "lookups" row displays three stats related to flow lookup triggered by
processing incoming packets in the datapath. "hit" displays number of packets
matches existing flows. "missed" displays the number of packets not matching any
existing flow and require user space processing. "lost" displays number of packets
destined for user space process but subsequently dropped before reaching userspace.
The sum of "hit" and "miss" equals to the total number of packets datapath
processed.
The "flows" row displays the number of flows in datapath.
The "masks" row displays the mega flow mask stats. This row is omitted for datapath
not implementing mega flow. "hit" displays the total number of masks visited for
matching incoming packets. "total" displays number of masks in the datapath.
"hit/pkt" displays the average number of masks visited per packet; the ratio
between "hit" and total number of packets processed by the datapath.
If one or more datapaths are specified, information on only those datapaths are
displayed. Otherwise, ovs-vswitchd displays information about all configured
datapaths.
DATAPATH FLOW TABLE DEBUGGING COMMANDS
The following commands are primarily useful for debugging Open vSwitch. The flow table
entries (both matches and actions) that they work with are not OpenFlow flow entries.
Instead, they are different and considerably simpler flows maintained by the Open vSwitch
kernel module. Do not use commands to add or remove or modify datapath flows if
ovs-vswitchd is running because it interferes with ovs-vswitchd's own datapath flow
management. Use ovs-ofctl(8), instead, to work with OpenFlow flow entries.
The dp argument to each of these commands is optional when exactly one datapath exists, in
which case that datapath is the default. When multiple datapaths exist, then a datapath
name is required.
dpctl/dump-flows [-m | --more] [--names | --no-names] [dp] [filter=filter] [type=type]
[pmd=pmd]
Prints to the console all flow entries in datapath dp's flow table. Without -m or
--more, output omits match fields that a flow wildcards entirely; with -m or
--more, output includes all wildcarded fields.
If filter=filter is specified, only displays the flows that match the filter.
filter is a flow in the form similiar to that accepted by ovs-ofctl(8)'s add-flow
command. (This is not an OpenFlow flow: besides other differences, it never
contains wildcards.) The filter is also useful to match wildcarded fields in the
datapath flow. As an example, filter='tcp,tp_src=100' will match the datapath flow
containing 'tcp(src=80/0xff00,dst=8080/0xff)'.
If pmd=pmd is specified, only displays flows of the specified pmd. Using pmd=-1
will restrict the dump to flows from the main thread. This option is only
supported by the userspace datapath.
If type=type is specified, only displays flows of the specified types. This option
supported only for ovs-appctl dpctl/dump-flows. type is a comma separated list,
which can contain any of the following:
ovs - displays flows handled in the ovs dp
tc - displays flows handled in the tc dp
dpdk - displays flows fully offloaded by dpdk
offloaded - displays flows offloaded to the HW
non-offloaded - displays flows not offloaded to the HW
partially-offloaded - displays flows where only part of their proccessing is
done in HW
all - displays all the types of flows
By default all the types of flows are displayed. ovs-dpctl always acts as if the
type was ovs.
dpctl/add-flow [dp] flow actions
dpctl/mod-flow [--clear] [--may-create] [-s | --statistics] [dp] flow actions
Adds or modifies a flow in dp's flow table that, when a packet matching flow
arrives, causes actions to be executed.
The add-flow command succeeds only if flow does not already exist in dp.
Contrariwise, mod-flow without --may-create only modifies the actions for an
existing flow. With --may-create, mod-flow will add a new flow or modify an
existing one.
If -s or --statistics is specified, then mod-flow prints the modified flow's
statistics. A flow's statistics are the number of packets and bytes that have
passed through the flow, the elapsed time since the flow last processed a packet
(if ever), and (for TCP flows) the union of the TCP flags processed through the
flow.
With --clear, mod-flow zeros out the flow's statistics. The statistics printed if
-s or --statistics is also specified are those from just before clearing the
statistics.
NOTE: flow and actions do not match the syntax used with ovs-ofctl(8)'s add-flow
command.
Usage Examples
Forward ARP between ports 1 and 2 on datapath myDP:
ovs-dpctl add-flow myDP \
"in_port(1),eth(),eth_type(0x0806),arp()" 2
ovs-dpctl add-flow myDP \
"in_port(2),eth(),eth_type(0x0806),arp()" 1
Forward all IPv4 traffic between two addresses on ports 1 and 2:
ovs-dpctl add-flow myDP \
"in_port(1),eth(),eth_type(0x800),\
ipv4(src=172.31.110.4,dst=172.31.110.5)" 2
ovs-dpctl add-flow myDP \
"in_port(2),eth(),eth_type(0x800),\
ipv4(src=172.31.110.5,dst=172.31.110.4)" 1
dpctl/add-flows [dp] file
dpctl/mod-flows [dp] file
dpctl/del-flows [dp] file
Reads flow entries from file (or stdin if file is -) and adds, modifies, or deletes
each entry to the datapath. Each flow specification (e.g., each line in file) may
start with add, modify, or delete keyword to specify whether a flow is to be added,
modified, or deleted. A flow specification without one of these keywords is treated
based on the used command. All flow modifications are executed as individual
transactions in the order specified.
dpctl/del-flow [-s | --statistics] [dp] flow
Deletes the flow from dp's flow table that matches flow. If -s or --statistics is
specified, then del-flow prints the deleted flow's statistics.
dpctl/get-flow [dp] ufid:ufid [-m | --more] [--names | --no-names]
Fetches the flow from dp's flow table with unique identifier ufid. ufid must be
specified as a string of 32 hexadecimal characters.
dpctl/del-flows [dp]
Deletes all flow entries from datapath dp's flow table.
DATAPATH FLOW CACHE COMMANDS
The following commands are useful for debugging and configuring the datapath flow cache
settings.
dpctl/cache-get-size [dp]
Prints the current cache sizes to the console.
dpctl/cache-set-size dp cache size
Set the dp's specific cache to the given size. The cache name can be found by
using the cache-get-size command.
CONNECTION TRACKING TABLE COMMANDS
The following commands are useful for debugging and configuring the connection tracking
table in the datapath.
The dp argument to each of these commands is optional when exactly one datapath exists, in
which case that datapath is the default. When multiple datapaths exist, then a datapath
name is required.
N.B.(Linux specific): the system datapaths (i.e. the Linux kernel module Open vSwitch
datapaths) share a single connection tracking table (which is also used by other kernel
subsystems, such as iptables, nftables and the regular host stack). Therefore, the
following commands do not apply specifically to one datapath.
dpctl/ipf-set-enabled [dp] v4|v6
dpctl/ipf-set-disabled [dp] v4|v6
Enables or disables IP fragmentation handling for the userspace connection tracker.
Either v4 or v6 must be specified. Both IPv4 and IPv6 fragment reassembly are
enabled by default. Only supported for the userspace datapath.
dpctl/ipf-set-min-frag [dp] v4|v6 minfrag
Sets the minimum fragment size (L3 header and data) for non-final fragments to
minfrag. Either v4 or v6 must be specified. For enhanced DOS security, higher
minimum fragment sizes can usually be used. The default IPv4 value is 1200 and the
clamped minimum is 400. The default IPv6 value is 1280, with a clamped minimum of
400, for testing flexibility. The maximum fragment size is not clamped, however,
setting this value too high might result in valid fragments being dropped. Only
supported for userspace datapath.
dpctl/ipf-set-max-nfrags [dp] maxfrags
Sets the maximum number of fragments tracked by the userspace datapath connection
tracker to maxfrags. The default value is 1000 and the clamped maximum is 5000.
Note that packet buffers can be held by the fragmentation module while fragments
are incomplete, but will timeout after 15 seconds. Memory pool sizing should be
set accordingly when fragmentation is enabled. Only supported for userspace
datapath.
dpctl/ipf-get-status [dp] [-m | --more]
Gets the configuration settings and fragment counters associated with the
fragmentation handling of the userspace datapath connection tracker. With -m or
--more, also dumps the IP fragment lists. Only supported for userspace datapath.
dpctl/dump-conntrack [-m | --more] [-s | --statistics] [dp] [zone=zone]
Prints to the console all the connection entries in the tracker used by dp. If
zone=zone is specified, only shows the connections in zone. With --more, some
implementation specific details are included. With --statistics timeouts and
timestamps are added to the output.
dpctl/flush-conntrack [dp] [zone=zone] [ct-tuple]
Flushes the connection entries in the tracker used by dp based on zone and
connection tracking tuple ct-tuple. If ct-tuple is not provided, flushes all the
connection entries. If zone=zone is specified, only flushes the connections in
zone.
If ct-tuple is provided, flushes the connection entry specified by ct-tuple in
zone. The zone defaults to 0 if it is not provided. The userspace connection
tracker requires flushing with the original pre-NATed tuple and a warning log will
be otherwise generated. An example of an IPv4 ICMP ct-tuple:
"ct_nw_src=10.1.1.1,ct_nw_dst=10.1.1.2,ct_nw_proto=1,icmp_type=8,icmp_code=0,icmp_id=10"
An example of an IPv6 TCP ct-tuple:
"ct_ipv6_src=fc00::1,ct_ipv6_dst=fc00::2,ct_nw_proto=6,ct_tp_src=1,ct_tp_dst=2"
dpctl/ct-stats-show [dp] [zone=zone] [-m | --more]
Displays the number of connections grouped by protocol used by dp. If zone=zone is
specified, numbers refer to the connections in zone. With --more, groups by
connection state for each protocol.
dpctl/ct-bkts [dp] [gt=threshold]
For each conntrack bucket, displays the number of connections used by dp. If
gt=threshold is specified, bucket numbers are displayed when the number of
connections in a bucket is greater than threshold.
dpctl/ct-set-maxconns [dp] maxconns
Sets the maximum limit of connection tracker entries to maxconns on dp. This can
be used to reduce the processing load on the system due to connection tracking or
simply limiting connection tracking. If the number of connections is already over
the new maximum limit request then the new maximum limit will be enforced when the
number of connections decreases to that limit, which normally happens due to
connection expiry. Only supported for userspace datapath.
dpctl/ct-get-maxconns [dp]
Prints the maximum limit of connection tracker entries on dp. Only supported for
userspace datapath.
dpctl/ct-get-nconns [dp]
Prints the current number of connection tracker entries on dp. Only supported for
userspace datapath.
dpctl/ct-enable-tcp-seq-chk [dp]
dpctl/ct-disable-tcp-seq-chk [dp]
Enables or disables TCP sequence checking. When set to disabled, all sequence
number verification is disabled, including for TCP resets. This is similar, but
not the same as 'be_liberal' mode, as in Netfilter. Disabling sequence number
verification is not an optimization in itself, but is needed for some hardware
offload support which might offer some performance advantage. Sequence number
checking is enabled by default to enforce better security and should only be
disabled if required for hardware offload support. This command is only supported
for the userspace datapath.
dpctl/ct-get-tcp-seq-chk [dp]
Prints whether TCP sequence checking is enabled or disabled on dp. Only supported
for the userspace datapath.
dpctl/ct-set-limits [dp] [default=default_limit] [zone=zone,limit=limit]...
Sets the maximum allowed number of connections in a connection tracking zone. A
specific zone may be set to limit, and multiple zones may be specified with a
comma-separated list. If a per-zone limit for a particular zone is not specified
in the datapath, it defaults to the default per-zone limit. A default zone may be
specified with the default=default_limit argument. Initially, the default per-
zone limit is unlimited. An unlimited number of entries may be set with 0 limit.
dpctl/ct-del-limits [dp] zone=zone[,zone]...
Deletes the connection tracking limit for zone. Multiple zones may be specified
with a comma-separated list.
dpctl/ct-get-limits [dp] [zone=zone[,zone]...]
Retrieves the maximum allowed number of connections and current counts per-zone.
If zone is given, only the specified zone(s) are printed. If no zones are
specified, all the zone limits and counts are provided. The command always
displays the default zone limit.
DPDK COMMANDS
These commands manage DPDK components.
dpdk/lcore-list
Lists the DPDK lcores and their cpu affinity. When RTE_MAX_LCORE lcores are
registered, some OVS PMD threads won't appear.
dpdk/log-list
Lists all DPDK components that emit logs and their logging levels.
dpdk/log-set [spec]
Sets DPDK components logging level. Without any spec, sets the logging level for
all DPDK components to debug. Otherwise, spec is a list of words separated by
spaces: a word can be either a logging level (emergency, alert, critical, error,
warning, notice, info or debug) or a pattern matching DPDK components (see
dpdk/log-list command on ovs-appctl(8)) separated by a colon from the logging level
to apply.
dpdk/get-malloc-stats
Prints the heap information statistics about DPDK malloc.
DPIF-NETDEV COMMANDS
These commands are used to expose internal information (mostly statistics) about the
"dpif-netdev" userspace datapath. If there is only one datapath (as is often the case,
unless dpctl/ commands are used), the dp argument can be omitted. By default the commands
present data for all pmd threads in the datapath. By specifying the "-pmd Core" option one
can filter the output for a single pmd in the datapath.
dpif-netdev/pmd-stats-show [-pmd core] [dp]
Shows performance statistics for one or all pmd threads of the datapath dp. The
special thread "main" sums up the statistics of every non pmd thread.
The sum of "phwol hits", "simple match hits", "emc hits", "smc hits", "megaflow
hits" and "miss" is the number of packet lookups performed by the datapath. Beware
that a recirculated packet experiences one additional lookup per recirculation, so
there may be more lookups than forwarded packets in the datapath.
The MFEX Opt hits displays the number of packets that are processed by the
optimized miniflow extract implementations.
Cycles are counted using the TSC or similar facilities (when available on the
platform). The duration of one cycle depends on the processing platform.
"idle cycles" refers to cycles spent in PMD iterations not forwarding any any
packets. "processing cycles" refers to cycles spent in PMD iterations forwarding at
least one packet, including the cost for polling, processing and transmitting said
packets.
To reset these counters use dpif-netdev/pmd-stats-clear.
dpif-netdev/pmd-stats-clear [dp]
Resets to zero the per pmd thread performance numbers shown by the dpif-netdev/pmd-
stats-show and dpif-netdev/pmd-perf-show commands. It will NOT reset datapath or
bridge statistics, only the values shown by the above commands.
dpif-netdev/pmd-perf-show [-nh] [-it iter_len] [-ms ms_len] [-pmd core] [dp]
Shows detailed performance metrics for one or all pmds threads of the user space
datapath.
The collection of detailed statistics can be controlled by a new configuration
parameter "other_config:pmd-perf-metrics". By default it is disabled. The run-time
overhead, when enabled, is in the order of 1%.
— used cycles
— forwared packets
— number of rx batches
— packets/rx batch
— max. vhostuser queue fill level
— number of upcalls
— cycles spent in upcalls
This raw recorded data is used threefold:
1. In histograms for each of the following metrics:
— cycles/iteration (logarithmic)
— packets/iteration (logarithmic)
— cycles/packet
— packets/batch
— max. vhostuser qlen (logarithmic)
— upcalls
— cycles/upcall (logarithmic) The histograms bins are divided linear or
logarithmic.
2. A cyclic history of the above metrics for 1024 iterations
3. A cyclic history of the cummulative/average values per millisecond wall
clock for the last 1024 milliseconds:
— number of iterations
— avg. cycles/iteration
— packets (Kpps)
— avg. packets/batch
— avg. max vhost qlen
— upcalls
— avg. cycles/upcall
The command options are:
-nh Suppress the histograms
-it iter_len
Display the last iter_len iteration stats
-ms ms_len
Display the last ms_len millisecond stats
The output always contains the following global PMD statistics:
Time: 15:24:55.270
Measurement duration: 1.008 s
pmd thread numa_id 0 core_id 1:
Iterations: 572817 (1.76 us/it)
- Used TSC cycles: 2419034712 ( 99.9 % of total cycles)
- idle iterations: 486808 ( 15.9 % of used cycles)
- busy iterations: 86009 ( 84.1 % of used cycles)
Rx packets: 2399607 (2381 Kpps, 848 cycles/pkt)
Datapath passes: 3599415 (1.50 passes/pkt)
- PHWOL hits: 0 ( 0.0 %)
- MFEX Opt hits: 3570133 ( 99.2 %)
- Simple Match hits: 0 ( 0.0 %)
- EMC hits: 336472 ( 9.3 %)
- SMC hits: 0 ( 0.0 %)
- Megaflow hits: 3262943 ( 90.7 %, 1.00 subtbl lookups/hit)
- Upcalls: 0 ( 0.0 %, 0.0 us/upcall)
- Lost upcalls: 0 ( 0.0 %)
Tx packets: 2399607 (2381 Kpps)
Tx batches: 171400 (14.00 pkts/batch)
Here "Rx packets" actually reflects the number of packets forwarded by the
datapath. "Datapath passes" matches the number of packet lookups as reported by the
dpif-netdev/pmd-stats-show command.
To reset the counters and start a new measurement use dpif-netdev/pmd-stats-clear.
dpif-netdev/pmd-perf-log-set on|off [-b before] [-a after] [-e|-ne] [-us usec] [-q qlen]
The userspace "netdev" datapath is able to supervise the PMD performance metrics
and detect iterations with suspicious statistics according to the following
criteria:
— The iteration lasts longer than usec microseconds (default 250). This can
be used to capture events where a PMD is blocked or interrupted for such a
period of time that there is a risk for dropped packets on any of its Rx
queues.
— The max vhost qlen exceeds a threshold qlen (default 128). This can be used
to infer virtio queue overruns and dropped packets inside a VM, which are
not visible in OVS otherwise.
Such suspicious iterations can be logged together with their iteration statistics
in the ovs-vswitchd.log to be able to correlate them to packet drop or other events
outside OVS.
The above command enables (on) or disables (off) supervision and logging at run-
time and can be used to adjust the above thresholds for detecting suspicious
iterations. By default supervision and logging is disabled.
The command options are:
-b before
The number of iterations before the suspicious iteration to be logged
(default 5).
-a after
The number of iterations after the suspicious iteration to be logged
(default 5).
-e Extend logging interval if another suspicious iteration is detected before
logging occurs.
-ne Do not extend logging interval if another suspicious iteration is detected
before logging occurs (default).
-q qlen
Suspicious vhost queue fill level threshold. Increase this to 512 if the
Qemu supports 1024 virtio queue length (default 128).
-us usec
Change the duration threshold for a suspicious iteration (default 250 us).
Note: Logging of suspicious iterations itself consumes a considerable amount of processing
cycles of a PMD which may be visible in the iteration history. In the worst case this can
lead OVS to detect another suspicious iteration caused by logging.
If more than 100 iterations around a suspicious iteration have been logged once, OVS falls
back to the safe default values (-b 5 -a 5 -ne) to avoid that logging itself continuously
causes logging of further suspicious iterations.
dpif-netdev/pmd-rxq-show [-pmd core] [dp]
For one or all pmd threads of the datapath dp show the list of queue-ids with port
names, which this thread polls.
dpif-netdev/pmd-rxq-rebalance [dp]
Reassigns rxqs to pmds in the datapath dp based on their current usage.
dpif-netdev/bond-show [dp]
When "other_config:lb-output-action" is set to "true", the userspace datapath
handles the load balancing of bonds directly instead of depending on flow
recirculation (only in balance-tcp mode).
When this is the case, the above command prints the load-balancing information of
the bonds configured in datapath dp showing the interface associated with each
bucket (hash).
dpif-netdev/subtable-lookup-prio-get
Lists the DPCLS implementations or lookup functions that are available as well as
their priorities.
dpif-netdev/subtable-lookup-prio-set lookup_function prio
Sets the priority of a lookup function by name, lookup_function, and priority,
prio, which should be a positive integer value. The highest priority lookup
function is used for classification.
The number of affected dpcls ports and subtables is returned.
dpif-netdev/dpif-impl-get
Lists the DPIF implementations that are available.
dpif-netdev/dpif-impl-set dpif_impl
Sets the DPIF to be used to dpif_impl. By default "dpif_scalar" is used.
dpif-netdev/miniflow-parser-get
Lists the miniflow extract implementations that are available.
dpif-netdev/miniflow-parser-set [-pmd core] miniflow_impl [study_cnt]
Sets the miniflow extract to miniflow_impl for a specified PMD or all PMDs in the
case where no value is specified. By default "scalar" is used. study_cnt defaults
to 128 and indicates the number of packets that the "study" miniflow implementation
must parse before choosing an optimal implementation.
DPIF-NETLINK COMMANDS
These commands are used to expose internal information of the "dpif-netlink" kernel space
datapath.
dpif-netlink/dispatch-mode
Displays the "dispatch-mode" for all datapaths.
NETDEV-DPDK COMMANDS
These commands manage DPDK related ports (type=dpdk*).
netdev-dpdk/set-admin-state [interface] up | down
Change the admin state for DPDK interface to up or down. If interface is not
specified, then it applies to all DPDK ports.
netdev-dpdk/detach pci-address
Detaches device with corresponding pci-address from DPDK. This command can be used
to detach device if it wasn't detached automatically after port deletion. Refer to
the documentation for details and instructions.
netdev-dpdk/get-mempool-info [interface]
Prints the debug information about memory pool used by DPDK interface. If called
without arguments, information of all the available mempools will be printed. For
additional mempool statistics enable CONFIG_RTE_LIBRTE_MEMPOOL_DEBUG while building
DPDK.
DATAPATH DEBUGGING COMMANDS
These commands query and modify datapaths. They are are similar to ovs-dpctl(8) commands.
dpif/show has the additional functionality, beyond dpctl/show of printing OpenFlow port
numbers. The other commands are redundant and will be removed in a future release.
dpif/dump-dps
Prints the name of each configured datapath on a separate line.
dpif/show
Prints a summary of configured datapaths, including statistics and a list of
connected ports. The port information includes the OpenFlow port number, datapath
port number, and the type. (The local port is identified as OpenFlow port 65534.)
dpif/dump-flows [-m] dp
Prints to the console all flow entries in datapath dp's flow table. Without -m,
output omits match fields that a flow wildcards entirely; with -m output includes
all wildcarded fields.
This command is primarily useful for debugging Open vSwitch. The flow table
entries that it displays are not OpenFlow flow entries. Instead, they are
different and considerably simpler flows maintained by the datapath module. If you
wish to see the OpenFlow flow entries, use ovs-ofctl dump-flows.
dpif/del-flows dp
Deletes all flow entries from datapath dp's flow table and underlying datapath
implementation (e.g., kernel datapath module).
This command is primarily useful for debugging Open vSwitch. As discussed in
dpif/dump-flows, these entries are not OpenFlow flow entries.
OFPROTO COMMANDS
These commands manage the core OpenFlow switch implementation (called ofproto).
ofproto/list
Lists the names of the running ofproto instances. These are the names that may be
used on ofproto/trace.
ofproto/trace [options] [dpname] odp_flow [packet]
ofproto/trace [options] bridge br_flow [packet]]
ofproto/trace-packet-out [options] [dpname] odp_flow [packet] actions
ofproto/trace-packet-out [options] bridge br_flow [packet] actions
Traces the path of an imaginary packet through switch and reports the path that it
took. The initial treatment of the packet varies based on the command:
• ofproto/trace looks the packet up in the OpenFlow flow table, as if the
packet had arrived on an OpenFlow port.
• ofproto/trace-packet-out applies the specified OpenFlow actions, as if the
packet, flow, and actions had been specified in an OpenFlow ``packet-out''
request.
The packet's headers (e.g. source and destination) and metadata (e.g. input port),
together called its ``flow,'' are usually all that matter for the purpose of
tracing a packet. You can specify the flow in the following ways:
dpname odp_flow
odp_flow is a flow in the form printed by ovs-dpctl(8)'s dump-flows command.
If all of your bridges have the same type, which is the common case, then
you can omit dpname, but if you have bridges of different types (say, both
ovs-netdev and ovs-system), then you need to specify a dpname to
disambiguate.
bridge br_flow
br_flow is a flow in the form similar to that accepted by ovs-ofctl(8)'s
add-flow command. (This is not an OpenFlow flow: besides other differences,
it never contains wildcards.) bridge names of the bridge through which
br_flow should be traced.
These commands support the following options:
--generate
Generate a packet from the flow (see below for more information).
--l7 payload
--l7-len length
Accepted only with --generate (see below for more information).
--consistent
Accepted by ofproto-trace-packet-out only. With this option, the command
rejects actions that are inconsistent with the specified packet. (An
example of an inconsistency is attempting to strip the VLAN tag from a
packet that does not have a VLAN tag.) Open vSwitch ignores most forms of
inconsistency in OpenFlow 1.0 and rejects inconsistencies in later versions
of OpenFlow. The option is necessary because the command does not
ordinarily imply a particular OpenFlow version. One exception is that, when
actions includes an action that only OpenFlow 1.1 and later supports (such
as push_vlan), --consistent is automatically enabled.
--ct-next flags
When the traced flow triggers conntrack actions, ofproto/trace will
automatically trace the forked packet processing pipeline with user
specified ct_state. This option sets the ct_state flags that the conntrack
module will report. The flags must be a comma- or space-separated list of
the following connection tracking flags:
• trk: Include to indicate connection tracking has taken place.
• new: Include to indicate a new flow.
• est: Include to indicate an established flow.
• rel: Include to indicate a related flow.
• rpl: Include to indicate a reply flow.
• inv: Include to indicate a connection entry in a bad state.
• dnat: Include to indicate a packet whose destination IP address has
been changed.
• snat: Include to indicate a packet whose source IP address has been
changed.
When --ct-next is unspecified, or when there are fewer --ct-next options
than ct actions, the flags default to trk,new.
Most commonly, one specifies only a flow, using one of the forms above, but
sometimes one might need to specify an actual packet instead of just a flow:
Side effects.
Some actions have side effects. For example, the normal action can update
the MAC learning table, and the learn action can change OpenFlow tables.
The trace commands only perform side effects when a packet is specified. If
you want side effects to take place, then you must supply a packet.
(Output actions are obviously side effects too, but the trace commands never
execute them, even when one specifies a packet.)
Incomplete information.
Most of the time, Open vSwitch can figure out everything about the path of a
packet using just the flow, but in some special circumstances it needs to
look at parts of the packet that are not included in the flow. When this is
the case, and you do not supply a packet, then a trace command will tell you
it needs a packet.
If you wish to include a packet as part of a trace operation, there are two ways to
do it:
--generate
This option, added to one of the ways to specify a flow already described,
causes Open vSwitch to internally generate a packet with the flow described
and then to use that packet. If your goal is to execute side effects, then
--generate is the easiest way to do it, but --generate is not a good way to
fill in incomplete information, because it generates packets based on only
the flow information, which means that the packets really do not have any
more information than the flow.
By default, for protocols that allow arbitrary L7 payloads, the generated
packet has 64 bytes of payload. Use --l7-len to change the payload length,
or --l7 to specify the exact contents of the payload.
packet This form supplies an explicit packet as a sequence of hex digits. An
Ethernet frame is at least 14 bytes long, so there must be at least 28 hex
digits. Obviously, it is inconvenient to type in the hex digits by hand, so
the ovs-pcap(1) and ovs-tcpundump(1) utilities provide easier ways.
With this form, packet headers are extracted directly from packet, so the
odp_flow or br_flow should specify only metadata. The metadata can be:
skb_priority
Packet QoS priority.
pkt_mark
Mark of the packet.
ct_state
Connection state of the packet.
ct_zone
Connection tracking zone for packet.
ct_mark
Connection mark of the packet.
ct_label
Connection label of the packet.
tun_id The tunnel ID on which the packet arrived.
in_port
The port on which the packet arrived.
The in_port value is kernel datapath port number for the first format and OpenFlow
port number for the second format. The numbering of these two types of port usually
differs and there is no relationship.
Usage examples:
Trace an unicast ICMP echo request on ingress port 1 to destination MAC
00:00:5E:00:53:01
ofproto/trace br in_port=1,icmp,icmp_type=8,\
dl_dst=00:00:5E:00:53:01
Trace an unicast ICMP echo reply on ingress port 1 to destination MAC
00:00:5E:00:53:01
ofproto/trace br in_port=1,icmp,icmp_type=0,\
dl_dst=00:00:5E:00:53:01
Trace an ARP request on ingress port 1
ofproto/trace br in_port=1,arp,arp_op=1
Trace an ARP reply on ingress port 1
ofproto/trace br in_port=1,arp,arp_op=2
VLOG COMMANDS
These commands manage ovs-vswitchd's logging settings.
vlog/set [spec]
Sets logging levels. Without any spec, sets the log level for every module and
destination to dbg. Otherwise, spec is a list of words separated by spaces or
commas or colons, up to one from each category below:
• A valid module name, as displayed by the vlog/list command on ovs-appctl(8),
limits the log level change to the specified module.
• syslog, console, or file, to limit the log level change to only to the
system log, to the console, or to a file, respectively.
On Windows platform, syslog is accepted as a word and is only useful along
with the --syslog-target option (the word has no effect otherwise).
• off, emer, err, warn, info, or dbg, to control the log level. Messages of
the given severity or higher will be logged, and messages of lower severity
will be filtered out. off filters out all messages. See ovs-appctl(8) for
a definition of each log level.
Case is not significant within spec.
Regardless of the log levels set for file, logging to a file will not take place
unless ovs-vswitchd was invoked with the --log-file option.
For compatibility with older versions of OVS, any is accepted as a word but has no
effect.
vlog/set PATTERN:destination:pattern
Sets the log pattern for destination to pattern. Refer to ovs-appctl(8) for a
description of the valid syntax for pattern.
vlog/list
Lists the supported logging modules and their current levels.
vlog/list-pattern
Lists logging patterns used for each destination.
vlog/close
Causes ovs-vswitchd to close its log file, if it is open. (Use vlog/reopen to
reopen it later.)
vlog/reopen
Causes ovs-vswitchd to close its log file, if it is open, and then reopen it.
(This is useful after rotating log files, to cause a new log file to be used.)
This has no effect unless ovs-vswitchd was invoked with the --log-file option.
vlog/disable-rate-limit [module]...
vlog/enable-rate-limit [module]...
By default, ovs-vswitchd limits the rate at which certain messages can be logged.
When a message would appear more frequently than the limit, it is suppressed. This
saves disk space, makes logs easier to read, and speeds up execution, but
occasionally troubleshooting requires more detail. Therefore,
vlog/disable-rate-limit allows rate limits to be disabled at the level of an
individual log module. Specify one or more module names, as displayed by the
vlog/list command. Specifying either no module names at all or the keyword any
disables rate limits for every log module.
The vlog/enable-rate-limit command, whose syntax is the same as
vlog/disable-rate-limit, can be used to re-enable a rate limit that was previously
disabled.
MEMORY COMMANDS
These commands report memory usage.
memory/show
Displays some basic statistics about ovs-vswitchd's memory usage. ovs-vswitchd
also logs this information soon after startup and periodically as its memory
consumption grows.
COVERAGE COMMANDS
These commands manage ovs-vswitchd's ``coverage counters,'' which count the number of
times particular events occur during a daemon's runtime. In addition to these commands,
ovs-vswitchd automatically logs coverage counter values, at INFO level, when it detects
that the daemon's main loop takes unusually long to run.
Coverage counters are useful mainly for performance analysis and debugging.
coverage/show
Displays the averaged per-second rates for the last few seconds, the last minute
and the last hour, and the total counts of all of the coverage counters.
coverage/read-counter counter
Displays the total count for the given coverage counter.
OPENVSWITCH TUNNELING COMMANDS
These commands query and modify OVS tunnel components.
ovs/route/add ipv4_address/plen output_bridge [GW]
Adds ipv4_address/plen route to vswitchd routing table. output_bridge needs to be
OVS bridge name. This command is useful if OVS cached routes does not look right.
ovs/route/show
Print all routes in OVS routing table, This includes routes cached from system
routing table and user configured routes.
ovs/route/del ipv4_address/plen
Delete ipv4_address/plen route from OVS routing table.
tnl/neigh/show
tnl/arp/show
OVS builds ARP cache by snooping are messages. This command shows ARP cache table.
tnl/neigh/set bridge ip mac
tnl/arp/set bridge ip mac
Adds or modifies an ARP cache entry in bridge, mapping ip to mac.
tnl/neigh/flush
tnl/arp/flush
Flush ARP table.
tnl/neigh/aging [seconds]
tnl/arp/aging [seconds]
Changes the aging time. The accepted values of seconds are between 1 and 3600. The
new entries will get the value as specified in seconds. For the existing entries,
the aging time is updated only if the current expiration is greater than seconds.
If used without arguments, it prints the current aging value.
tnl/egress_port_range [num1] [num2]
Set range for UDP source port used for UDP based Tunnels. For example VxLAN. If
case of zero arguments this command prints current range in use.
OPENFLOW IMPLEMENTATION
This section documents aspects of OpenFlow for which the OpenFlow specification requires
documentation.
Packet buffering.
The OpenFlow specification, version 1.2, says:
Switches that implement buffering are expected to expose, through documentation,
both the amount of available buffering, and the length of time before buffers may
be reused.
Open vSwitch does not maintains any packet buffers.
Bundle lifetime
The OpenFlow specification, version 1.4, says:
If the switch does not receive any OFPT_BUNDLE_CONTROL or OFPT_BUNDLE_ADD_MESSAGE
message for an opened bundle_id for a switch defined time greater than 1s, it may
send an ofp_error_msg with OFPET_BUNDLE_FAILED type and OFPBFC_TIMEOUT code. If
the switch does not receive any new message in a bundle apart from echo request and
replies for a switch defined time greater than 1s, it may send an ofp_error_msg
with OFPET_BUNDLE_FAILED type and OFPBFC_TIMEOUT code.
Open vSwitch implements default idle bundle lifetime of 10 seconds. (This is configurable
via other-config:bundle-idle-timeout in the Open_vSwitch table. See ovs-
vswitchd.conf.db(5) for details.)
LIMITS
We believe these limits to be accurate as of this writing. These limits assume the use of
the Linux kernel datapath.
• ovs-vswitchd started through ovs-ctl(8) provides a limit of 65535 file descriptors.
The limits on the number of bridges and ports is decided by the availability of
file descriptors. With the Linux kernel datapath, creation of a single bridge
consumes three file descriptors and each port consumes one additional file
descriptor. Other platforms may have different limitations.
• 8,192 MAC learning entries per bridge, by default. (This is configurable via
other-config:mac-table-size in the Bridge table. See ovs-vswitchd.conf.db(5) for
details.)
• Kernel flows are limited only by memory available to the kernel. Performance will
degrade beyond 1,048,576 kernel flows per bridge with a 32-bit kernel, beyond
262,144 with a 64-bit kernel. (ovs-vswitchd should never install anywhere near
that many flows.)
• OpenFlow flows are limited only by available memory. Performance is linear in the
number of unique wildcard patterns. That is, an OpenFlow table that contains many
flows that all match on the same fields in the same way has a constant-time lookup,
but a table that contains many flows that match on different fields requires lookup
time linear in the number of flows.
• 255 ports per bridge participating in 802.1D Spanning Tree Protocol.
• 32 mirrors per bridge.
• 15 bytes for the name of a port, for ports implemented in the Linux kernel. Ports
implemented in userspace, such as patch ports, do not have an arbitrary length
limitation. OpenFlow also limit port names to 15 bytes.
SEE ALSO
ovs-appctl(8), ovsdb-server(1).