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Redundant WAN link

I have two 2611 routers, one at each of two physical locations. Each location has a T-1 link to an ISP plus a private T-1 that connects the two. What I want to achieve is- if one external T-1 (ISP) link fails all trafftic will be routed through the private T-1 and out to the ISP on the second router (and visa versa). I want to keep it simple as possible so--can I set two gateways of last resort (one with a high administrative cost) on each router and be done, or do I have to use RIP, IGRP, or other do get the job done. Any suggestions?

Thanks in advance,



Re: Redundant WAN link

Static routes and Default routes to internet, would be just fine, for your network.

Two default routes one pointing to primary T1 and the other pointing to secondary T1 with a ahiger administrative costs would be fine. Also you need static routes to reach from one location to another, via the private line.

The only problem with this configuration, is that there would be a routing loop in case of the primary link fails at both the sites, the second default route will kick in at both the routers, and all packets going to internet would be bounced between the two routers, on the private T1, until their TTL dies out.

But this is acceptable, because when both line fails, at either sites, there is no other way out to the internet.

Re: Redundant WAN link

You have a two options, one being the default static route with higher admin distance pointing to the T1 link and the other using eigrp. Static routing in your case would seem to be the easiest and most efficient choice. Static default routes would only take 2 commands on each router, go with that.


New Member

Re: Redundant WAN link

Thanks to both of you for your replies! Static it is.



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