Ospf multiple area problem

[Ahmed Chowdhury]

hi ,

      i have 7 routers in my wan topology. one router is hub(HQ) and rest of the are spokes(Branches). i configured gre over Ipsec vpn.now

how do i configure them in multiple ospf area so that my HQ router will be area 0 and the branches are like 2, 3, 4 area. i also want that my branch routers dont receive all HQ routes. in this case i have to do stub area but i also read that stub area is only blocking external routes and i dont have any external routes. so what should i do now. thanks in advanceee...

[Yasir Ashfaque]

Hi,

Just configure it as totally stubby area, as your Spokes will be in different areas,  HQ will only advertise the summary default route to spokes.

Yasir

[Ahmed Chowdhury]

Thanks bro one more question is that now  the local lan of the  hub will be area 0 and the respective branch tunnels(WAN) will be different area.rite..correct me if i am wrong.thanks in advancee..

[Yasir Ashfaque]

Yes, it will work in this way too.

[Ahmed Chowdhury]

Thanks bro and one more thing is that multiple ospf is working fine.then i configured the spokes as totally-stubby but then i cant ping any other remote branches. any suggestions will be really appriciatable.thanks in advanceeee.

[Yasir Ashfaque]

Can you share the output of following commands, on HQ and any two spoke.

show ip ospf interface brief

show ip ospf nei

show ip route ospf

[Ahmed Chowdhury]

HUB Router:

HUB-Router#show ip ospf interface brief
Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Fa1/0        10    0               192.168.1.1/24     1     DR    0/0
Tu1          10    1               200.200.200.2/30   11111 P2P   1/1
Tu2          10    2               200.200.200.6/30   11111 P2P   1/1
Tu3          10    3               200.200.200.10/30  11111 P2P   1/1

HUB-Router#sh ip ospf nei

Neighbor ID     Pri   State           Dead Time   Address         Interface
200.200.200.1     0   FULL/  -        00:00:33    200.200.200.1   Tunnel1
200.200.200.5     0   FULL/  -        00:00:36    200.200.200.5   Tunnel2
200.200.200.9     0   FULL/  -        00:00:36    200.200.200.9   Tunnel3

HUB-Router#sh ip route ospf

O    192.168.13.0/24 [110/11112] via 200.200.200.5, 00:07:20, Tunnel2

O    192.168.36.0/24 [110/11112] via 200.200.200.1, 00:07:20, Tunnel1

O    192.168.53.0/24 [110/11112] via 200.200.200.9, 00:07:30, Tunnel3

SPOKE-1

SPOKE-1#show ip ospf interface brief

Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Tu0          10    1               200.200.200.1/30   11111 P2P   1/1
Fa1/0        10    1               192.168.36.1/24    1     DR    0/0

SPOKE-1#sh ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
200.200.200.10    0   FULL/  -        00:00:29    200.200.200.2   Tunnel0

SPOKE-1#sh ip route ospf
     200.200.200.0/30 is subnetted, 3 subnets
O IA    200.200.200.8 [110/22222] via 200.200.200.2, 00:11:44, Tunnel0
O IA    200.200.200.4 [110/22222] via 200.200.200.2, 00:11:44, Tunnel0
O IA 192.168.13.0/24 [110/22223] via 200.200.200.2, 00:11:38, Tunnel0
O IA 192.168.53.0/24 [110/22223] via 200.200.200.2, 00:11:44, Tunnel0
O IA 192.168.1.0/24 [110/11112] via 200.200.200.2, 00:11:44, Tunnel0

SPOKE-2

SPOKE-2#sh ip ospf int br
Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C
Tu0          10    2               200.200.200.5/30   11111 P2P   1/1
Fa1/0        10    2               192.168.13.1/24    1     DR    0/0

SPOKE-2#sh ip ospf nei

Neighbor ID     Pri   State           Dead Time   Address         Interface
200.200.200.10    0   FULL/  -        00:00:32    200.200.200.6   Tunnel0

SPOKE-2#sh ip route ospf
     200.200.200.0/30 is subnetted, 3 subnets
O IA    200.200.200.8 [110/22222] via 200.200.200.6, 00:13:49, Tunnel0
O IA    200.200.200.0 [110/22222] via 200.200.200.6, 00:13:49, Tunnel0
O IA 192.168.36.0/24 [110/22223] via 200.200.200.6, 00:13:44, Tunnel0
O IA 192.168.53.0/24 [110/22223] via 200.200.200.6, 00:13:49, Tunnel0
O IA 192.168.1.0/24 [110/11112] via 200.200.200.6, 00:13:49, Tunnel0

[Yasir Ashfaque]

Hi,

I think you have not configured it as totally stubby, and from the routing table things seems to be ok.

[Ahmed Chowdhury]

Thanks a lot buddy. now its working finee.thankssss..............