Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
New Member

PI space with NSSA static route redistribution


Recently I have encountered a problem while trying to implement NSSA area on a part of our network.

After redistributing static routes and connected with "subnets" keywords, the routers (ASR) were  not  able to see the static route with mask /24 in their routing table as N2 rouyte type, hence the external routes were not reachable by the routers sitting in the backbone.

The rest of the routes - connected and more specific subnets i.e. /25 were ok, only /24 caused the problems.

We have found two solutions to this problem:

1. We break the /24 in two /25 static pointing to the clients subnets reachable via these static routes

2. As we were using SVIs on the switches (6500) we have trunked the vlans (SVIs) outside NSSA area and re-terminated SVI with IP addresses on the device in the Backbone 0so end-to-end connectivity was passing over Layer 2 link and bypassing OSPF NSSA (of course as we were redistributing connected - SVIs too in this case - we were seeing them in the backbone).

Is there any specific reason why NSSA does not redistribute /24 static subnets outside to backbone 0 ?

Could it be a software bug ? If so, why /25 does work ?



PI space with NSSA static route redistribution

I think it should work. Maybe there's a forward address problem.

Can you give the output of a "sh ip ospf data nssa-ext " on the ASBR and a "sh ip ospf data ext " on a area 0 router?

New Member

PI space with NSSA static route redistribution

This is already resolved.

CreatePlease to create content