How to configure static ARP in Cisco router

How to configure static ARP in Cisco router

There might be a time when your Cisco Router might not learn a ARP on an IP and MAC.

This normally happens if you're doing a Network Load Balancing using Multicast.

1. Log in to the Router in Global Configuration Mode

2. Type... arp <ip address of target> <MAC address> arpa

<ip address of target> is the IP of your host, for which arp is not being learned automatically

<MAC address> is the MAC address of your NIC card on that host, But you have to enter it like in example below:

MAC = 11:aa:22:bb:33:cc

Enter it like = 11aa.22bb.33cc

So in an example, if your host is 192.168.1.200 and mac is 11.aa.22.bb.33.cc the command would be.

arp 192.168.1.200 11aa.22bb.33cc arpa

If you're doing a NLB and need to find the MAC address, then open the NLB Manager and right click on the Cluster and go into Cluster Properties -> Cluster Parameters and In Network Address Box you would find the MAC address.