A network administrator is configuring the routers in the graphic for OSPF. The OSPF process has been started and the networks have been configured for Area 0 as shown in the diagram. The network administrator has several options for configuring RouterB to ensure that it will be preferred as the designated router (DR) for the 172.16.1.0 /24 LAN segment. What configuration tasks could be used to establish this preference? (Choose three.)
A. Configure the priority value of the Fa0/0 interface of RouterB to a higher value than any other interface on the Ethernet network.
B. Change the router id of Router B by assigning the IP address 172.16.1.130/24 to the Fa0/0 interface of RouterB.
C. Configure a loopback interface on RouterB with an IP address higher than any IP address on the other routers.
D. Change the priority value of the Fa0/0 interface of RouterB to zero.
E. Change the priority values of the Fa0/0 interfaces of RouterA and RouterC to zero.
F. No further configuration is necessary.
I think its F
I’ve set this up in GNS3 and Router B is already the DR without any configuration. That is because 198.18.0.10/15 on Router B is the highest IP address.
RouterC#sh ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.10.254 1 FULL/DROTHER 00:00:35 172.16.1.124 GigabitEthernet0/0
198.18.0.101 1 FULL/DR 00:00:33 172.16.1.123 GigabitEthernet0/0
RouterA#sh ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.11.254 1 FULL/BDR 00:00:33 172.16.1.125 GigabitEthernet0/0
198.18.0.101 1 FULL/DR 00:00:30 172.16.1.123 GigabitEthernet0/0