GLBP and backup AVG

[mahesh18]

Hi Everyone,

Say For GLBP if we have 2 routers one is AVG with  and other is Standby AVG.

Both are also AVF.

Now if we add 3rd Router in Group what will it become it will be ?

For sure it will be   AVF.

Need to know will it become backup AVG ????????????

Also need to confirm if Standby AVG and Backup AVG  mean same thing ???????????

Thanks

MAhesh

[Reza Sharifi · Accepted solution]

Hi Mahesh,

The 3rd router will become AVF.

Have a look:

GLBP elects an Active Virtual Gateway (AVG). The job of the AVG is to  assign virtual MAC addresses to each of the other GLBP routers and to  assign each network host to one of the GLBP routers.

The routers that receive this MAC address assignment are known as Active Virtual Forwarders (AVF).

here is the link:

http://www.cisco.com/en/US/prod/collateral/iosswrel/ps6537/ps6554/ps6600/product_data_sheet0900aecd803a546c.html

also:

http://blog.ine.com/2008/04/24/glbp-explained/

HTH

Reza

[Gabriel Hill · Accepted solution]

Hello Mahesh,

If the AVG fails, the AVF's participate in an election.

1. The highest priority will take the AVG's role
2. If the priority is the same, the router with the highest IP address becomes the AVG

For Reference

http://www.cisco.com/en/US/docs/ios/12_2t/12_2t15/feature/guide/ft_glbp.html

[mahesh18]

Hi Reza & Gabriel,

I read the documents it says that every  group has 1 AVG and one standby AVG.

I need to know do we have also backup AVG?

Is backup AVG is same as standby AVG?

Thanks

Mahesh

[Gabriel Hill · Accepted solution]

Yes, backup AVG = standby AVG.

The standby / backup AVG (referred to as SVG) will take over for the AVG if it fails. A new standby / backup AVG will be elected if there are more AVF's in the group (based on priority, then ip address).

Hope this clears up the confusion.

-Gabriel

[mahesh18]

Hi Gabriel,

Now my confusion is clear.

Many thanks for reply back.

Best regards

Mahesh