Hi All, I am hoping somebody can offer some advice here as my brain doesn't seem to be able to function correctly at this point in time.....
Currently we have one main upstream transit provider, we talk to them using BGP from our primary border router, we only receive a default route from them as we really don't need anything else at this stage.
Internally we use OSPF for routing around our network, so the OSPF config on that border router is told to distribute the default route, everything works fine, all the routers know to get out to the net they go through that border router.
We now want to configure our secondary border router with another upstream transit provider as a backup, we will use BGP to connect to them also on this second router, it is also part of the internal OSPF network like the primary border router.
What I can't get my brain to work out is how to I setup the OSPF on this secondary router so that I can propagate the default route from that at a higher distance or whatever so that all the internal routers know they can get out there if the primary one fails, but only if it fails.
On the secondary we are prepending our AS to make it look less desirable as we really only want this for emergencies and won't provision enough capacity to use it as a daily driver.
Currently we run the following settings in the OSPF instance on the primary router:
Redistribute Default Route - always (as type 1)
Redistribute Connected Routes - as type 1
Everything else is set to no, metrics are set to defaults, we also run filtering which is configured to keep things correct.
I am thinking that we may need to use some OSPF filters to increase the cost of the secondary default route but I was hoping somebody may be able to advise what settings I will need and what will work the best in this scenario which is really just a backup transit connection.
Thanks in advance !
Regards
Paul
