OSPF stub node config?

[pashdown1]

I am looking for a sample config for the following network as I have been tearing my hair out trying to get this to work:

(Router A) ----- (Router B)

        \              /

         (Router C)

               |

         (Router D)

Router D should only know about a default route from Router C.  Router C should only know about the default routes, plus connected and static networks from Router A & B, plus the connected and static networks on Router D.   Router's A & B should know about the connected and static networks on C&D.

I've tried using the stub node and area configs and summaries and usually I end up with nothing or everything on Router D.  My config looks like this right now and I'm getting nothing:

Router C:

router ospf 1234

log-adjacency-changes

area 100 stub no-summary

redistribute connected subnets

redistribute static subnets

passive-interface default

no passive-interface ATM1/1/0.10

no passive-interface ATM1/1/0.11

network 10.2.3.72 0.0.0.3 area 100

network 10.2.3.80 0.0.0.3 area 100

Router D:

router ospf 1234

log-adjacency changes

redistribute connected subnets

redistribute static subnets

passive-interface default

no passive-interface Serial0/0.1

no passive-interface Serial0/1.1

network 10.2.3.72 0.0.0.3 area 100

network 10.2.3.80 0.0.0.3 area 100

routerd#show ip ospf neighbors

(nothing)

[Jon Marshall · Accepted solution]

Pete

Presumably routers A & B are in a different area ?

First things first you need to add this line to router D OSPF config -

area 100 stub no-summary

because all routers in a stub area need to know they are in a stub area. Can you add that and then you should see an OSPF neighborship between C & D.

Jon

[pashdown1]

I would like to eventually have A & B in different areas, but right now they are both 0.0.0.0.  I presume it would be best if the relationships between each router was a different area?

Thanks for the tip, that brought it up.

[Jon Marshall]

If you want router D to only receive a default-route then you need to configure it as a totally stub area. But if you want C to receive connected networks from A & B then C must share an area with A & B that is not a totally stub area. So yes, you would need at least 2 areas for it to work as you want.

Jon      

[pashdown1]

With:

"area 100 stub no-summary"

on both C & D, I am getting a default from D, but I'm not getting D's connected networks showing up in OSPF on C.  If I reduce D to "area 100 stub", I still don't get anything on C.  Any ideas?

[Jon Marshall]

Can you post full configs of C & D ?

Jon

[pashdown1]

I figured it out.  I didn't realize that the network statement needed to cover subnets that you wanted to advertise as well as subnets you were advertising on.  I set the network area 100 on D to 0.0.0.0 255.255.255.255 and the connected subnet advertised.

Thank you for your help.