Provided by: iproute2_6.1.0-1ubuntu2_amd64 bug

NAME

       ip-nexthop - nexthop object management

SYNOPSIS

       ip [ ip-OPTIONS ] nexthop  { COMMAND | help }

       ip nexthop { show | flush } SELECTOR

       ip nexthop { add | replace } id ID NH

       ip nexthop { get | del } id ID

       ip nexthop bucket list BUCKET_SELECTOR

       ip nexthop bucket get id ID index INDEX

       SELECTOR := [ id ID ] [ dev DEV ] [ vrf NAME ] [ master DEV ] [ groups ] [ fdb ]

       BUCKET_SELECTOR := SELECTOR  | [ nhid ID ]

       NH := { blackhole | [ via ADDRESS ] [ dev DEV ] [ onlink ] [ encap ENCAP ] [ fdb ] | group
               GROUP [ fdb ] [ type TYPE [ TYPE_ARGS ] ] }

       ENCAP := [ ENCAP_MPLS ]

       ENCAP_MPLS := mpls [ LABEL ] [ ttl TTL ]

       GROUP := id[,weight[/...]

       TYPE := { mpath | resilient }

       TYPE_ARGS := [ RESILIENT_ARGS ]

       RESILIENT_ARGS := [ buckets BUCKETS ] [ idle_timer IDLE ] [ unbalanced_timer UNBALANCED ]

DESCRIPTION

       ip nexthop is used to manipulate entries in the kernel's nexthop tables.

       ip nexthop add id ID
              add new nexthop entry

       ip nexthop replace id ID
              change the configuration of a nexthop or add new one

              via [ FAMILY ] ADDRESS
                     the address of the nexthop router, in the address family FAMILY.  Address
                     family must match address family of nexthop instance.

              dev NAME
                     is the output device.

              onlink pretend that the nexthop is directly attached to this link, even if it does
                     not match any interface prefix.

              encap ENCAPTYPE ENCAPHDR
                     attach tunnel encapsulation attributes to this route.

                     ENCAPTYPE is a string specifying the supported encapsulation type. Namely:

                             mpls - encapsulation type MPLS

                     ENCAPHDR is a set of encapsulation attributes specific to the ENCAPTYPE.

                             mpls
                               MPLSLABEL - mpls label stack with labels separated by /

                               ttl TTL - TTL to use for MPLS header or 0 to inherit from IP
                               header

              group GROUP [ type TYPE [ TYPE_ARGS ] ]
                     create a nexthop group. Group specification is id with an optional weight
                     (id,weight) and a '/' as a separator between entries.

                     TYPE is a string specifying the nexthop group type. Namely:

                             mpath - Multipath nexthop group backed by the hash-threshold
                             algorithm. The default when the type is unspecified.

                             resilient - Resilient nexthop group. Group is resilient to addition
                             and deletion of nexthops.

                     TYPE_ARGS is a set of attributes specific to the TYPE.

                             resilient
                               buckets BUCKETS - Number of nexthop buckets. Cannot be changed for
                               an existing group

                               idle_timer IDLE - Time in seconds in which a nexthop bucket does
                               not see traffic and is therefore considered idle. Default is 120
                               seconds

                               unbalanced_timer UNBALANCED - Time in seconds in which a nexthop
                               group is unbalanced and is therefore considered unbalanced. The
                               kernel will try to rebalance unbalanced groups, which might result
                               in some flows being reset. A value of 0 means that no rebalancing
                               will take place. Default is 0 seconds

              blackhole
                     create a blackhole nexthop

              fdb    nexthop and nexthop groups for use with layer-2 fdb entries.  A fdb nexthop
                     group can only have fdb nexthops.  Example: Used to represent a vxlan remote
                     vtep ip. layer-2 vxlan fdb entry pointing to an ecmp nexthop group
                     containing multiple remote vtep ips.

       ip nexthop delete id ID
              delete nexthop with given id.

       ip nexthop show
              show the contents of the nexthop table or the nexthops selected by some criteria.

              dev DEV
                     show the nexthops using the given device.

              vrf NAME
                     show the nexthops using devices associated with the vrf name

              master DEV
                     show the nexthops using devices enslaved to given master device

              groups show only nexthop groups

              fdb    show only fdb nexthops and nexthop groups

       ip nexthop flush
              flushes nexthops selected by some criteria. Criteria options are the same as show.

       ip nexthop get id ID
              get a single nexthop by id

       ip nexthop bucket show
              show the contents of the nexthop bucket table or the nexthop buckets selected by
              some criteria.

              id ID
                     show the nexthop buckets that belong to a nexthop group with a given id

              nhid ID
                     show the nexthop buckets that hold a nexthop with a given id

              dev DEV
                     show the nexthop buckets using the given device

              vrf NAME
                     show the nexthop buckets using devices associated with the vrf name

              master DEV
                     show the nexthop buckets using devices enslaved to given master device

       ip nexthop bucket get id ID index INDEX
              get a single nexthop bucket by nexthop group id and bucket index

EXAMPLES

       ip nexthop ls
           Show all nexthop entries in the kernel.

       ip nexthop add id 1 via 192.168.1.1 dev eth0
           Adds an IPv4 nexthop with id 1 using the gateway 192.168.1.1 out device eth0.

       ip nexthop add id 2 encap mpls 200/300 via 10.1.1.1 dev eth0
           Adds an IPv4 nexthop with mpls encapsulation attributes attached to it.

       ip nexthop add id 3 group 1/2
           Adds a nexthop with id 3. The nexthop is a group using nexthops with ids 1 and 2 at
           equal weight.

       ip nexthop add id 4 group 1,5/2,11
           Adds a nexthop with id 4. The nexthop is a group using nexthops with ids 1 and 2 with
           nexthop 1 at weight 5 and nexthop 2 at weight 11.

       ip nexthop add id 5 via 192.168.1.2 fdb
           Adds a fdb nexthop with id 5.

       ip nexthop add id 7 group 5/6 fdb
           Adds a fdb nexthop group with id 7. A fdb nexthop group can only have fdb nexthops.

       ip nexthop add id 10 group 1/2 type resilient buckets 32
           Add a resilient nexthop group with id 10 and 32 nexthop buckets.

SEE ALSO

       ip(8)

AUTHOR

       Original Manpage by David Ahern <dsahern@kernel.org>