Which two possible issues can prevent the tunnel from coming up?

You are troubleshooting an issue with a GRE tunnel between R1 and R2 and find that routing is OK on all intermediary routers. The tunnel is up on R1, but down on R2.

Which two possible issues can prevent the tunnel from coming up? (Choose Two)
A . The tunnel does not come up unless traffic is sent through it.
B . The tunnel source interface is down on R2.
C . No specific route interface is down on R2
D . R2 does not know how to reach the tunnel destination.
E . The tunnel keep alive timer doesn’t match on R1 and R2.

View Answer

Answer: BD