1IP-NEXTHOP(8) Linux IP-NEXTHOP(8)
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6 ip-nexthop - nexthop object management
7
9 ip [ ip-OPTIONS ] nexthop { COMMAND | help }
10 ip nexthop { show | flush } SELECTOR
13 ip nexthop { add | replace } id ID NH
15 ip nexthop { get | del } id ID
17 ip nexthop bucket list BUCKET_SELECTOR
19 ip nexthop bucket get id ID index INDEX
21 SELECTOR := [ id ID ] [ dev DEV ] [ vrf NAME ] [ master DEV ] [ groups
23 ] [ fdb ]
24 BUCKET_SELECTOR := SELECTOR | [ nhid ID ]
26 NH := { blackhole | [ via ADDRESS ] [ dev DEV ] [ onlink ] [ encap EN‐
28 CAP ] [ fdb ] | group GROUP [ fdb ] [ type TYPE [ TYPE_ARGS ] ]
29 }
30 ENCAP := [ ENCAP_MPLS ]
32 ENCAP_MPLS := mpls [ LABEL ] [ ttl TTL ]
34 GROUP := id[,weight[/...]
36 TYPE := { mpath | resilient }
38 TYPE_ARGS := [ RESILIENT_ARGS ]
40 RESILIENT_ARGS := [ buckets BUCKETS ] [ idle_timer IDLE ] [ unbal‐
42 anced_timer UNBALANCED ]
43
46 ip nexthop is used to manipulate entries in the kernel's nexthop ta‐
47 bles.
48 ip nexthop add id ID
50 add new nexthop entry
51 ip nexthop replace id ID
53 change the configuration of a nexthop or add new one
54 via [ FAMILY ] ADDRESS
56 the address of the nexthop router, in the address family
57 FAMILY. Address family must match address family of nex‐
58 thop instance.
59 dev NAME
61 is the output device.
62 onlink pretend that the nexthop is directly attached to this
64 link, even if it does not match any interface prefix.
65 encap ENCAPTYPE ENCAPHDR
67 attach tunnel encapsulation attributes to this route.
68 ENCAPTYPE is a string specifying the supported encapsula‐
70 tion type. Namely:
71 mpls - encapsulation type MPLS
73 ENCAPHDR is a set of encapsulation attributes specific to
75 the ENCAPTYPE.
76 mpls
78 MPLSLABEL - mpls label stack with labels sepa‐
79 rated by /
80 ttl TTL - TTL to use for MPLS header or 0 to
83 inherit from IP header
84 group GROUP [ type TYPE [ TYPE_ARGS ] ]
87 create a nexthop group. Group specification is id with an
88 optional weight (id,weight) and a '/' as a separator be‐
89 tween entries.
90 TYPE is a string specifying the nexthop group type.
92 Namely:
93 mpath - Multipath nexthop group backed by the
95 hash-threshold algorithm. The default when the
96 type is unspecified.
97 resilient - Resilient nexthop group. Group is re‐
99 silient to addition and deletion of nexthops.
100 TYPE_ARGS is a set of attributes specific to the TYPE.
103 resilient
105 buckets BUCKETS - Number of nexthop buckets.
106 Cannot be changed for an existing group
107 idle_timer IDLE - Time in seconds in which a
110 nexthop bucket does not see traffic and is
111 therefore considered idle. Default is 120 sec‐
112 onds
113 unbalanced_timer UNBALANCED - Time in seconds
115 in which a nexthop group is unbalanced and is
116 therefore considered unbalanced. The kernel
117 will try to rebalance unbalanced groups, which
118 might result in some flows being reset. A value
119 of 0 means that no rebalancing will take place.
120 Default is 0 seconds
121 blackhole
124 create a blackhole nexthop
125 fdb nexthop and nexthop groups for use with layer-2 fdb en‐
127 tries. A fdb nexthop group can only have fdb nexthops.
128 Example: Used to represent a vxlan remote vtep ip.
129 layer-2 vxlan fdb entry pointing to an ecmp nexthop group
130 containing multiple remote vtep ips.
131 ip nexthop delete id ID
134 delete nexthop with given id.
135 ip nexthop show
138 show the contents of the nexthop table or the nexthops selected
139 by some criteria.
140 dev DEV
142 show the nexthops using the given device.
143 vrf NAME
145 show the nexthops using devices associated with the vrf
146 name
147 master DEV
149 show the nexthops using devices enslaved to given master
150 device
151 groups show only nexthop groups
153 fdb show only fdb nexthops and nexthop groups
155 ip nexthop flush
157 flushes nexthops selected by some criteria. Criteria options are
158 the same as show.
159 ip nexthop get id ID
162 get a single nexthop by id
163 ip nexthop bucket show
166 show the contents of the nexthop bucket table or the nexthop
167 buckets selected by some criteria.
168 id ID
170 show the nexthop buckets that belong to a nexthop group
171 with a given id
172 nhid ID
174 show the nexthop buckets that hold a nexthop with a given
175 id
176 dev DEV
178 show the nexthop buckets using the given device
179 vrf NAME
181 show the nexthop buckets using devices associated with
182 the vrf name
183 master DEV
185 show the nexthop buckets using devices enslaved to given
186 master device
187 ip nexthop bucket get id ID index INDEX
190 get a single nexthop bucket by nexthop group id and bucket index
191
194 ip nexthop ls
195 Show all nexthop entries in the kernel.
196 ip nexthop add id 1 via 192.168.1.1 dev eth0
198 Adds an IPv4 nexthop with id 1 using the gateway 192.168.1.1 out
199 device eth0.
200 ip nexthop add id 2 encap mpls 200/300 via 10.1.1.1 dev eth0
202 Adds an IPv4 nexthop with mpls encapsulation attributes attached to
203 it.
204 ip nexthop add id 3 group 1/2
206 Adds a nexthop with id 3. The nexthop is a group using nexthops
207 with ids 1 and 2 at equal weight.
208 ip nexthop add id 4 group 1,5/2,11
210 Adds a nexthop with id 4. The nexthop is a group using nexthops
211 with ids 1 and 2 with nexthop 1 at weight 5 and nexthop 2 at weight
212 11.
213 ip nexthop add id 5 via 192.168.1.2 fdb
215 Adds a fdb nexthop with id 5.
216 ip nexthop add id 7 group 5/6 fdb
218 Adds a fdb nexthop group with id 7. A fdb nexthop group can only
219 have fdb nexthops.
220 ip nexthop add id 10 group 1/2 type resilient buckets 32
222 Add a resilient nexthop group with id 10 and 32 nexthop buckets.
223
225 ip(8)
226
229 Original Manpage by David Ahern <dsahern@kernel.org>
230iproute2 30 May 2019 IP-NEXTHOP(8)