Question

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

a) Yes
b) No

Answer 1

In OSPF, if the "router-id" command is not set manually, the protocol selects the highest IP address of the loopback interfaces as the router ID. If no loopback interfaces are present, the highest active interface IP address is used.

Step-by-step explanation:

If the "router-id" command has not been entered in an OSPF configuration, the Open Shortest Path First (OSPF) protocol will use the IP address of the highest-numbered loopback interface as the router ID (RID). If there are no loopback interfaces configured, OSPF will choose the highest IP address among the router's active interfaces. In the context of OSPF, the router ID is a 32-bit value used to uniquely identify a router within an OSPF network. It is crucial during the OSPF process for establishing adjacencies and exchanging routing information.