OSPF. 2 BDR

Question:

Can anyone explain me, C2951-VSEC why in my network topology, where OSPF is running, i have 2 BDR router, instead of have 1 BDR and one DROTHER.

On DR router i have following output:

CENTRE#show ip ospf neighbor


Neighbor ID     Pri   State           Dead Time   Address         Interface
172.16.10.150     1   FULL/BDR        00:00:31    192.168.10.1    FastEthernet0/0
172.16.10.50      1   FULL/BDR        00:00:33    192.168.10.10   FastEthernet0/1

Answer:

A DR/BDR is elected for each multiaccess network, not for the network as a whole. You have two FastEthernet interfaces and hence (at least) two multiaccess networks. On each of these networks, DR and BDR must be elected. That is why you see two Cisco 3925 BDRs - because each of them serves a different multiaccess network. This is normal. For more info, please refer to http://lilirouter.metroblog.com/