ip-nexthop - nexthop object management

Author

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

iproute2                                           30 May 2019                                     IP-NEXTHOP(8)

Description

ipnexthop 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.

devNAME
is the output device.

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

encapENCAPTYPEENCAPHDR
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.mplsMPLSLABEL - mpls label stack with labels separated by /ttlTTL - TTL to use for MPLS header or 0 to inherit from IP header

groupGROUP[typeTYPE[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.resilientbucketsBUCKETS - Number of nexthop buckets. Cannot be changed for an existing
group

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

unbalanced_timerUNBALANCED - 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.

devDEV
show the nexthops using the given device.

vrfNAME
show the nexthops using devices associated with the vrf name

masterDEV
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.

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

nhidID
show the nexthop buckets that hold a nexthop with a given id

devDEV
show the nexthop buckets using the given device

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

masterDEV
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.

Name

       ip-nexthop - nexthop object management

Synopsis

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

       ipnexthop { show | flush } SELECTORipnexthop { add | replace } id IDNHipnexthop { get | del } id IDipnexthopbucketlistBUCKET_SELECTORipnexthopbucketget id ID index INDEXSELECTOR := [ idID ] [ devDEV ] [ vrfNAME ] [ masterDEV ] [ groups ] [ fdb ]

       BUCKET_SELECTOR := SELECTOR  | [ nhidID ]

       NH := { blackhole | [ viaADDRESS ] [ devDEV ] [ onlink ] [ encapENCAP ] [ fdb ] | groupGROUP [
               hw_stats { on | off }  ] [ fdb ] [ typeTYPE [ TYPE_ARGS ] ] }

       ENCAP := [ ENCAP_MPLS ]

       ENCAP_MPLS := mpls [ LABEL ] [ ttlTTL ]

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

       TYPE := { mpath | resilient }

       TYPE_ARGS := [ RESILIENT_ARGS ]

       RESILIENT_ARGS := [ bucketsBUCKETS ] [ idle_timerIDLE ] [ unbalanced_timerUNBALANCED ]