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BGP Load Balancing through multiple routers to multiple ISP's

We have a cisco 3640 connected to two ISPs and BGP is enabled and it is working fine.The Router is connected to a pix firewall. We wanted to add a new T1 line in another router and confiugre BGP for the same and have complete redudancy on all these. Please let me know how can i acheive with one Pix firewall and two routers with 3 T1 and BGP Configured.

Thanks in Advance


Re: BGP Load Balancing through multiple routers to multiple ISP'

It should be as simple as adding the second router, and having them run iBGP between themselves in front of the pix, and havin the pix learn the default from the two routers, rather than having a static default pointing to the one router.

is where I'd start for a sample configuration.



New Member

Re: BGP Load Balancing through multiple routers to multiple ISP'

Thanks a lot for your reply. We have already in place one Cisco 3640 router running BGP between two isps. Now all i need to do is connect the second router and configure ibgp between the new connection with the existing 2 connections. Am i correct? The existing cisco 3640 router has one fast ethernet interface and i have added both the isps ip address like x.x.x1 as primary and y.y.y.y1 as secondary and this is directly connected to the cisco pix which is having an outside ip address of x.x.x.x2.

Now when i add the new router which has its ethernet interface as z.z.z.z1. In this case i will place a hub/switch inbetween the routers and the cisco pix. The outside interface(x.x.x2) will be connected to the hub and ethernet interface x.x.x.x1,y.y.y.y1 and z.z.z.z1 will also be connected to the same hub. Will this work or should i go for another firewall for the new t1 line and terminate both the internal network using a router behind pix firewall?

Can you please advice me show should i proceed.

Thanks in Advance

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