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IP-NEXTHOP(8) Linux IP-NEXTHOP(8)

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

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

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

ENCAP := [ ENCAP_MPLS ]

ENCAP_MPLS := mpls [ LABEL ] [ ttl TTL ]

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

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
create a nexthop group. Group specification is id with an optional weight (id,weight) and a '/' as a separator between entries.
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

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.

SEE ALSO

ip(8)

AUTHOR

Original Manpage by David Ahern <dsahern@kernel.org>
30 May 2019 iproute2