Load Balance using BGP with different two ISPs.

[ahmed.hatem]

Hi All,

I need help to setup load balance between two different ISPs connected to the one router in the branch and two different router in the HQ, we need to load balance the traffic between the two ISPs, we are using BGP with both ISPs, anyone can help?

[Julio E. Moisa]

Hi

Assuming the links are equal cost you can set up maximum-paths 2 at the HQ. 

Now if the links have different bandwidth you can include on the HQ routers:

bgp dmzlink-bw

neighbor x.x.x.x dmzlink-bw

If the branch router is connected to 2 different AS you can use:

maximum-paths 2

bgp bestpath as-path mutipath-relax  (note: it is a hidden BGP command, so TAB will not complete the word)

If you can share a diagram it will be useful. 

Hope it is useful

:-)

[RGill94]

To go along with Julios comment, if you are going to use maximum-paths for ECMP make sure your BGP attributes for each ECMP desired route are the same as it relates to the best path selection process.

1. Weight

2. local-pref

3. as-path length

4. origin

5. MED

6. eBGP over iBGP

7. IGP Cost to next hop

[Georg Pauwen]

Hello,

in addition to Julio's post, also have a look at the link below. Check topology 4, which I think matches yours. There are several different sample configurations that accomplish redundancy as well...

http://showipbgp.com/bgp-configurations/cisco.html

[Kolanjiyappan Kaliyamoorthy]

Hi ahmed.hatem ,
Using PBR,U can do the load balancing.
Please refer the below link,you will get better idea.
http://www.ciscozine.com/pbr-route-a-packet-based-on-source-ip-address/

[paul driver]

Hello
Without knowing you topology its hard to provide a definitive answer - Can you post a topology diagram please.

How is the Branch rtr connecting to HQ - either ISP or via a p2p connection and then uses the isps for wan connectivity?

res
Paul

[ahmed.hatem]

I have uploaded the topology diagram.

Thanks.