ospf for multi exit points

[sudhakar.aleti]

Hi Gurus,

Need a suggestion as we have two campus where i have to configure OSPF between the core switches and i have two exist points from these two campus, any link goes down the connectivity has no loss need to take care

R1 and R2 are in a single campus

R3 and R4 are in a single campus

R1 has a default Route towards R5

R4 has a default Route towards R6

Need to configure OSPF between these devices

Please suggest 

Thanks

Sudhakar

[Joseph W. Doherty]

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Posting

Not quite sure what you're looking to resolve.  Is there a reason why you cannot run OSPF between all the connected routers?

Is the issue, the two off-site exits use defaults?  If so, have your exit edge routers originate OSPF defaults.

[sudhakar.aleti]

Hi Joseph,

Sorry i was not clear, but my requiremnet is

we have two campus in one locations, and each campus has connected with branch office via NLD links and from both the campus we have internet exit points for broswing and i need to configure ospf between these two campus and make 2 default routes at internet exit points.

and orginate the default routes into the ospf for branch office to reach capmus 1 and campus 2 for general browsing (internet).

At the same time i am looking for failover of exit points.

Please let me know if still i am not clear.

Thanks

Sudhakar

[Giuseppe Larosa]

Hello Sudhakar,

having two exit points to the Internet the best choice is to use O E1 routes that take in account both external seed metric and internal metric to reach the ASBR (the router that injects the default route in OSPF in your case).

you can use use

route-map DEFAULT permit 10

set metric-type 1

set metric 50

on devices with static default routes to exit points:

router ospf 10

default-information originate route-map DEFAULT

Hope to help

Giuseppe