High Availability neighbor¶

High Availability neighbor enables synchronizing ARP/NDP entries between two HA nodes in master/backup mode.

If the activity is switched between the two nodes, the new active node will be able to take over dataplane traffic and synchonize its new ARP/NDP entries with the inactive node.

The activity of a node can be controlled by CLI commands or by external applications (such as the VRRP service).

In this example, ARP/NDP entries learned by the ha1 (the master) will be sent to ha2 (the backup) through eth3.

HA neighbor parameters are configured in the ha-neighbor context:

ha1 running config# vrf main ha-neighbor
ha1 running ha-neighbor#!

Configure the ha1:

ha1 running ha-neighbor#! node-id 1
ha1 running ha-neighbor#! interface eth3
ha1 running ha-neighbor#! local-address 10.150.0.1
ha1 running ha-neighbor#! listen-ha-group ha-group1
ha1 running ha-neighbor#

node-id is a unique identifier for this node in the HA cluster. It ranges from 1 to 15.
interface is the network interface on which synchronization packets are exchanged
local-address is the IPv4 or IPv6 addresses of the other HA node.
listen-ha-group is the high-availability group that controls the activity state of this HA node. See High-availability Groups for more information.

Display ha1 HA neighbor state:

ha1 running ha-neighbor# show state
ha-neighbor
    enabled true
    node-id 1
    local-address 10.150.0.1
    listen-ha-group ha-group1
    interface eth3
    state master
    ..

On ha2, the node-id, interface and the local-address must be adjusted:

ha2 running config# vrf main ha-neighbor
ha2 running ha-neighbor#! node-id 2
ha2 running ha-neighbor#! interface eth3
ha2 running ha-neighbor#! local-address 10.150.0.2
ha2 running ha-neighbor#! listen-ha-group ha-group1
ha2 running ha-neighbor#

Display ha2 HA neighbor state:

ha2 running ha-neighbor# show state
ha-neighbor
    enabled true
    node-id 2
    local-address 10.150.0.2
    listen-ha-group ha-group1
    interface eth3
    state backup
    ..