[j-nsp] ISIS-OSPF Redistribution Questions

[Walaa Abdel razzak]

Hi Experts

 

If you have area 2 nssa receiving default route from the ABR with metric 150, two routers R6, R7 are sending this default route to ISIS level 1 router in the DC. The L1 external preference are modified on R6, R7 to be 149. This is to prefer routes coming from ISIS than OSPF. The problem is that DC router resend the default route from R6 to R7. R7 see it with preference of 149 and the default route is coming from OSPF is 150 so it prefers the ISIS which cause non-optimal routing. Any ideas to solve this issue without making modification on the DC router?

 

Sample config:

 

R6 or R7 config.:

--------------------

isis {

    export senddefault;           --------à send default to the ISIS router

    level 2 disable;

    level 1 external-preference 149;

    interface fe-1/3/1.23;

    interface lo0.6;

}

ospf {

    export fromisis;                 --------à redistribute routes from ISIS

    area 0.0.0.2 {

        nssa;

        interface lo0.6;

        interface fe-1/3/0.20;

        interface fe-1/3/1.16;

        interface fe-1/3/1.23 {

            passive;

        }

    }

}

 

DC:

-----

isis {

    export static-isis;

    level 2 disable;

    interface fe-1/3/0.23;

    interface fe-1/3/0.24;

}

  

BR,

Walaa Abdel Razzak