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New Member

Multiple GLBP for 1 FastEthernet Interface

Good Day Experts!

I would like to ask some help regarding GLBP configuration.

I have two 3745 routers, one as primary and the other is redundant. Both are configured to have 3 E1 links from 3 different telcos. E1 links in the redundant router, well of course, serves as backup for the respective primary E1 links. I attached a diagram for this querry.

So the configuration for each router goes like this:


Telco1 Primary E1 - Serial 0/0

Telco2 Primary E1 - Serial 0/1

Telco3 Primary E1 - Serial 0/2


Telco1 Redundant E1 - Serial 0/0

Telco2 Redundant E1 - Serial 0/1

Telco3 Redundant E1 - Serial 0/2

I want to configure GLBP for each Telco for redundancy and load balancing. So, if I will implement this on each routers will I be able to use only 1 FastEthernet for all the GLBP implementation on 3 Telco E1 links? or Do I really need to have 1 FastEthernet interface for each GLBP implementation?

If I can do with only 1 FE, can someone help me on how to configure this. It would be highly appreciated if someone can help me on this one. Thanks

New Member

Re: Multiple GLBP for 1 FastEthernet Interface

In short yes, just create a glbp group 1, 2 and 3, then track the serial interfaces. If this is internet facing, I would highly suggest using Ibgp between the 2 routers.

New Member

Re: Multiple GLBP for 1 FastEthernet Interface

Thanks a lot murphymd for the reply. Highly appreciated.

New Member

Re: Multiple GLBP for 1 FastEthernet Interface

Sorry, one interface on each router is fine.