OSPF different default routes for different areas

[hagnerfaxed]

Site 1 Router A: ABR (Area 0, Area 1) >>>>>ISP A and ISP B <<<<< Site 2 Router A: (Area 1)

Five Layer 3 switches connected to Site 1 Router A. Five Layer 3 switches connected to Site 2 Router A

Site 1 and Site 2 are connected over 2 ISP using 2 tunnels (192.168.1.0 /30) and (192.168.2.0 /30)

Site 1 Router A is configured with default routes to ISP and ISP2 and default information originate

The problem is that the default routes advertised to Site 2 Router A (Area 1) are traversing the tunnels instead of using direct connections to ISP A and ISP B

r/Cisco - OSPF different default routes for different areas
My question is, is it possible to assign different default routes to different area (Site 2 Router A) so that the default traffic will not go through the tunnels to backbone area first then to the ISP?

Thank you so much for your advice.

[MHM Cisco World]

there are many solution 
1- use front door to separate the IGP run over Tunnel and the IGP/Static route use by router to connect to ISP
2- use NSSA for IGP over tunnel this area will prevent any LSA5 (default LSA5)
3- use BGP over tunnel and use route-map to prevent default route advertise from one site to other site 

MHM

[paul driver]

Hello
Can you share a topology diagram..

[Giuseppe Larosa]

Hello @hagnerfaxed ,

>> The problem is that the default routes advertised to Site 2 Router A (Area 1) are traversing the tunnels instead of using direct connections to ISP A and ISP B

Your Site 2 Router A should have static default routes to ISP A, ISP B with AD < 110  ( default OSPF AD) and this will fix your issue.

Either you have floating static defaul routes with AD > 110 or you have only specific routes for remote public IP address(es) of Site 1 Router A.

As suggested making OSPF area 1 of type NSSA will block the sending of LSA type 5 over the two tunnels, however if these default LSA are used in the Site 2 Router A this means they are preferred over existing static default routes as I have explained above.

Hope to help

Giuseppe