High Availability with HSRP & GLBP

[mtechnology]

I have a Point to point network running between US and India and i want to make it highly available either by using HSRP / GLBP. For this we are adding routers at both the ends and a redundant link

I have attached the existing and the proposed connectivity with HSRP or GLBP.

What iam confused about is whether i should run HSRP/GLBP at both sides or not. If i do not run it at both ends, how the traffic will load balance ?

thanks in advance

[mtechnology]

Sorry missed the attachment in my earlier post

[mihanlin]

Hello and thank you for your question.

HSRP/GLBP is used on Ethernet networks to provide a redundant gateway address. Therefore you should run it on both sites.

You would configure hosts in network A to use the HSRP/GLBP ip address of the US routers, and the hosts on network B to use the HSRP/GLBP ip address of the India routers.

You would then typically run a dynamic routing protocol over the WAN links to load balance traffic over the serial connections. Note that EIGRP, RIP2 and OSPF to name a few support load balancing.

Hope this makes sense. If not, please let me know if I can explain further.

Also note that HSRP isn't typically a load balancing protocol, just a redundancy mechanism - as only one router is active for a particular network at any one time.

Kind regards,

Michael Hanline

Customer Support Engineer - Cisco TAC

[amit-singh]

Hi Friend,

You should Run GLBP in the proposed scenario. The reason is that both the routers will be activ and will participate in packet forwarding to the remote side. This will utilize both the links to the other side in forwarding the traffic thus resulting in a cost effective usage of both the leased line circuit.

HTH,

-amit singh

[mtechnology]

Thanks Amit and Michael for the inputs.

I understand running a routing protocol for loadbalancing on the wan links would be the best option.

Is it possible to use static routing and achieve the desired results.

Now if i use GLBP then dont u think the packet can go from one to another via one link and the return would be from another link?

Any config examples wouls be appreciated in this scenario

thanks in advance

[amit-singh]

Hi Friend,

You can use either the static routing or the routing protocol. Both will work in this scenario.

With the GLBP and the per-destination loadbalancing enabled (which is default on the router) the router will maintain the track of the route that it has used for a particular destination. The router will use the same link as far as the detsination address is same.

Here is the document for the GLBP configuration.

http://www.ciscoblog.com/docstore/haipglbp.pdf

HTH,

-amit singh