Question about HSRP

Take a look at this doc:

Thanks for the reply Steve but this document doesn't give any information on what the "secondary virtual ip address" is used for. What purpose does it serve in lieu of the fact that there is already a virtual ip address configured. What is purpose does a secondary virtual ip address serve?

The article for which you provided the link had only the following information which doesn't offer an explanation of this parameter (see below)...

" All secondary virtual IP addresses are listed on separate lines. If one of the virtual IP addresses is a duplicate of an address configured for another device, it will be marked as "duplicate." A duplicate address indicates that the router has failed to defend its ARP (Address Resolution Protocol) cache entry. "

Regards,

Adil

It serves the same purpose as a secondary IP address on a regular interface. If you have multiple logical subnets on the LAN, the router needs an address in each subnet. When you're using HSRP, you need virtual IPs in each subnet, and secondary virtual IPs are used for the additional ones.

However, I can't really think of a good reason to have a secondary VIP in the same subnet as the primary VIP, as in your example.

I used it a couple of times during migration windows in complex environments. If you have to collapse a gateway for a destination on an other gateway and unfortunately you have to face with a lot of statics, even on hosts, I found that a very quick way to do that is to turn off the gateway and immediately add the old gateway ip to the new gateway as a vip, this gives you all the time of the world to find all the statics, remove or change it one at a time, then completely remove the vip. Bye, Tosh.

Virtual Ip address is used for HSRP

Go through following link for working of HSRP:

AN wrote: