Question

Refer to the exhibit. If the switch reboots and all routers have to re-establish OSPF adjacencies, which routers will become the new DR and BDR?

A. Router R2 will become the DR, and Router R4 will become the BDR.
B. Router R1 will become the DR, and Router R3 will become the BDR.
C. Router R4 will become the DR, and Router R3 will become the BDR.
D. Router R3 will become the DR, and Router R2 will become the BDR.

Answer 1

The new DR and BDR are determined based on OSPF priority values assigned to each router.

Step-by-step explanation:

When the switch reboots and all routers have to re-establish OSPF adjacencies, the new DR and BDR are determined based on the OSPF priority values assigned to each router. The router with the highest priority becomes the DR, and the router with the second highest priority becomes the BDR.

In the given exhibit, the priority values are as follows:

• Router R1: Priority 100
• Router R2: Priority 0
• Router R3: Priority 1
• Router R4: Priority 1

Since Router R1 has the highest priority, it will become the DR. Router R3 and R4 both have the same priority, but R3 has the higher router ID (IP address), so it will become the BDR.