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New Member



my question:

i have a router, which is connected to two different areas -100 and 200.

Now i want taht a certain loopbackadress is propageted to both areas.

i tried with two ospf prozeßes and configured the lo-interface in both prozeßes

on withe area 100 - the other with area 200.

i had no problem to configure this - but the lo-address was only propagated into one area ?

How can i achive this ??

Any idea ?

Thanks for an answer !

  • Other Network Infrastructure Subjects
New Member

Re: OSPF-Problem

For 2 areas to communicate they have to go through area 0 which is the bacbone area. Do you have bacbone are configured ?

New Member

Re: OSPF-Problem

What we want to do is the following:

Our router has two ospf processes and we want to put one loopback-interface into both processes

looks similarly to this:

int loopback0

ip address

router ospf 1

network area 0

router ospf 2

network area 0

! works if one process is defined with "redistribute connected subnets"

! but this should not be necessary, right?

The reason for this is that we connect two autonomous MP-BGP-systems (carrier-to-carrier) both via OSPF over this router and need one tdp-router-id which is propagated into both networks.

Any suggestions how we should design it right?



Cisco Employee

Re: OSPF-Problem

What wrong with redistribute connected subnets? If you are worrying about unecessary type 5 generation then do it with a route-map. If you are running the latest IOS code which has a fix for CSCdp72526 then this will be automatically taken care of, no need for a route-map.

The configuration you mentioned will not work because the interface can only be configured in one ospf process and in one area.


New Member

Re: OSPF-Problem


how would you configure getting one loopback-address (=one tdp router-id for both) into two different ospf systems?

Sample would be fine,

Regards Chris

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