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New Member

PRI backup for 2 Serial Links


How do i configure an PRI interface, so that it acts as a backup interface(will dial to different network) to 2 E1 links. I am using OSPF and both the E1 links are in load balancing fashion. I cannot configure multilink because i am using a E1 to V.35 converter to connect the E1 to Serial interface in the router. It was not working when i configured multilink. I want the backup PRI to take over only if both the links go down. Please Help..

Thanks in Advance

New Member

Re: PRI backup for 2 Serial Links

Just place a floating static route in your config and define interesting traffic so that your link is not kept up indefinately. You can search CCO for more examples but since your using ospf your "show ip route" would look like the following; via E1 (110/10)

via E2 (110/10)

When the routes drop, the floating static would kick in and look like the following; via PRI1 (200/100)

There are several ways to accomplish what your looking for but this is my favorite method. Hope this helps

New Member

Re: PRI backup for 2 Serial Links


Thanks for the reply. I found another way. it is to use dialer watch-group command and then define lets say the loopback address of the router that i want to watch using the dialer watch-list command.

Best Regards

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