OSPF connectivity but no DR/BDR

boxerboy1168

I have an OSPF lab built in GNS3. My routers are showing all the proper routes in the routing table and I am able to ping the specific interfaces yet my #show ip ospf neighbor command is not showing a DR / BDR on any of my routers.



This is my lab. Here is a #show ip ospf neighbor, #show ip route and #show run for R2.

R2#show ip ospf nei


Neighbor ID Pri State Dead Time Address Interface
4.4.4.4 0 FULL/ - 00:00:34 10.1.3.1 Serial0/2
1.1.1.1 0 FULL/ - 00:00:34 10.1.2.1 Serial0/1
3.3.3.3 0 FULL/ - 00:00:35 10.1.1.1 Serial0/0

#sh ip route

Gateway of last resort is not set


10.0.0.0/24 is subnetted, 5 subnets
C 10.1.3.0 is directly connected, Serial0/2
C 10.1.2.0 is directly connected, Serial0/1
C 10.1.1.0 is directly connected, Serial0/0
O IA 10.1.5.0 [110/128] via 10.1.3.1, 00:23:27, Serial0/2
O IA 10.1.4.0 [110/128] via 10.1.1.1, 00:23:27, Serial0/0

#show run (OSPF related)


router ospf 1
router-id 2.2.2.2
log-adjacency-changes
network 10.1.1.2 0.0.0.0 area 0
network 10.1.2.2 0.0.0.0 area 0
network 10.1.3.2 0.0.0.0 area 0

The OSPF configuration is exactly the same on the other routers but with correct IP's and router-id's.

Any ideas?

d4nz1g

serial interfaces have a default of p2p ospf network. no dr/bdr is elected in p2p links since there is no purpose on having a dr on a p2p link.

show ip ospf int s0/0 so you can see the network type

boxerboy1168

ok thanks, is there a way to disable p2p on serial links or do I need to add a router with an FA connection to play with the DR/BDR process?

d4nz1g

yes, you can configure the ospf network types with the "ip ospf network-tpe" interface command. both sides must match, as the flooding process is different between p2p and broadcast (when you see dr/bdr)

you could use a FA interface as ethernet interfaces are considered of type broadcast by default.