[c-nsp] Does "backup interface" gratuitous ARP?

[Sam Stickland]

Hi,

I'm exploring redundancy possibilities for a router hand off without a
dynamic routing protocol. It's ugly and I'm not going to explain all the
details here, but I basically have this configuration on a router:

interface Gi1/1
  backup interface Gi1/2
  ip address 192.168.1.1 255.255.255.252

interface Gi1/2
  ip address 192.168.1.1 255.255.255.252

If interface Gi1/1 goes down will the router send a gratuitous ARP when
interface Gi1/2 comes up? I seem to remember that it's default IOS
behaviour to always send a gratuitous ARP when an interface first comes up.

I don't have test hardware to hand and I can't simulate this in GNS because
ethernet interfaces are permanently up in dynamips.

Regards,

Sam