Route monitoring for dynamic routes in cluster

You can use a route monitor to make a Cluster node dependent on the internal routing table whether it contains or does not contain dynamically learnt route. In a Cluster system, a route monitor on each node checks the internal routing table to ensure there is a route entry for reaching a particular network is always present. If the route entry is not present, the state of the route monitor changes to DOWN.

In a cluster deployment, if the client-side or server side-link of a node goes down, traffic is steered to this node through the peer nodes for processing. The steering of traffic is implemented by configuring dynamic routing and adding static ARP entries, pointing to the special MAC address of each node, on all the nodes. If there are a large number of nodes in a cluster deployment, adding and managing static ARP entries with special MAC addresses on all the nodes is a cumbersome task. Now, nodes implicitly use special MAC addresses for steering packets. Therefore, static ARP entries pointing to special MAC addresses are no longer required to be added to the cluster nodes.

To bind a cluster node using the command line interface

At the command prompt, type:

bind cluster node <nodeId> (-routeMonitor <ip_addr|ipv6_addr|*> [<netmask>])
unbind cluster node <nodeId> (-routeMonitor <ip_addr|ipv6_addr|*> [<netmask>])

Consider a scenario where Node 1 is bound to route monitor 1.1.1.0 255.255.255.0. When a dynamic route fails, Node 1 become INACTIVE. Health status is available in the Show Cluster Node command by node id as show below.  

Node ID: 1
IP:  10.102.169.96
Backplane:  1/1/2
Health: NOT UP
Reason(s): Route Monitor(s) of the node have failed
Route Monitor -  Network: 1.1.1.0   Netmask: 255.255.255.0   State: DOWN

Route monitoring for dynamic routes in cluster