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New Member

isdn backup using routing protocols

Hi all, If I have 2 routers 1 with a primary rate e1, and the other one is an isdn router, they are using hsrp, and the primary one is the primary rate e1. as far as routing goes what would you do to trigger the isdn? static routes, or using routing protocols? and would I track wan the interface on the primary router so if it goes down the backup becomes active ?


Re: isdn backup using routing protocols

Hi Carl,

Firstly yes you want to track the wan interface on the primary router so that it decrements hsrp priority enough for secondary to become active.

Secondly, on the secondary router I would just config a static route with high admin distance ie, 200, pointing to isdn dialer interface. So normally the remote site routes get installed into route table via igp from primary router, the static route wont take effect until these routes via igp are gone, because wan interface on primary has gone down, so now static to isdn is installed into route table on secondary router, and secondary router is also hsrp active, in order for other routers to route to remote site routes, you must also config to redistribute static route into igp on secondary.




New Member

Re: isdn backup using routing protocols

can you please give me an example config of this at all ?