Routing preferences question

Jack Bates jbates at brightok.net
Wed Jan 29 14:31:46 UTC 2003


> Does anybody know how/if I can force cisco router to consider ospf route
> (I'll consider other igp protocol if its possible) from particular source
> to be prefereble over connected and locally-entered static routes. This is
> needed for failover project I'm doing. Please note that especially big
> question is with "connected" route through subinterface, which I can't
> find any way to override with igp, for static I could at least make them
> learned igp routes.
>
You can change the administrative distance/protocol priorities, but I think
this only works for everything but connected. If I'm not mistaken (not at a
router) connected is set to 0 and can't be changed. What you are proposing
is dangerous. There's usually a better way to handle a backup. I'm guessing
that you have a distant connection at least two hops away that when it goes
down you want to activate a pvc into a frame or atm cloud. If all end points
in such a cloud are routers, it's best to use a routing protocol across the
cloud and make the routes unprefered. When the other routes go down, the new
routes come up. With statics, the administrative distance is the last
number. In BGP, we often set our null routes to 254 or 255 so that the null
route is NEVER prefered over another route.

Jack Bates
BrightNet Oklahoma




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