Ospf RID

[St0nE]

You work as network administrator at ABC.

Your trainee is configuring a router with both physical and logical interfaces.

He asks you what factor determines the OSPF router ID.

What should you tell him?

A. The lowest network number of any interface.

B. The lowest IP address of any logical interface.

C. The lowest IP address of any physical interface.

D. The highest network number of any interface.

E. The highest IP address of any logical interface.

F. The highest IP address of any physical interface.

Wouldnt the answer to this question be E?

Thanks

[netops01]

Yes.

If loopback interfaces have been configured then OSPF will use the highest loopback address as the Router ID even if the highest loopback address is smaller than the IP address of any active physical interface.

Ian

[gajoseph]

well strictly speaking it is probably answer F.

E says "any logical interface" a loopback interface is just one type of logical interface.

[Georg Pauwen]

Hello,

if this is a Cisco question, or anything similar to a Cisco exam question, the answer is definitely E. IMHO, with logical interfaces they are referring only to loopbacks, but the wording of the question makes you think that, as you said, there are other types of logical interfaces. From my experience with Cisco questions I would say that too much creative thinking leads to the wrong answer...)

Regards,

GP