Question

If the "router-id" command has not been entered, OSPF will use the loopback interface with the highest/lowest IP address to assign it's RID.

a. True
b. False

Answer 1

The statement is true; OSPF uses the highest IP address of the loopback interfaces to assign its router ID if the "router-id" command has not been entered.

Step-by-step explanation:

If the "router-id" command has not been entered, OSPF will use the loopback interface with the highest IP address to assign its RID. This statement is true. If no loopback interface is present, OSPF will choose the highest IP address among the router's active interfaces as the router ID. The choice of the router ID is critical as it uniquely identifies a router within an OSPF network and is used in the OSPF routing algorithm.

If the "router-id" command has not been entered in OSPF, the router will use the loopback interface with the highest IP address to assign the router ID.

For example, if we have three loopback interfaces with IP addresses 192.168.1.1, 10.0.0.1, and 172.16.0.1, OSPF will choose 192.168.1.1 as the router ID because it has the highest IP address.

To answer the question, the statement is TRUE.