Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) — Question 184

The following system log message is presented after a network administrator configures a GRE tunnel:
%TUN-RECURDOWN Interface Tunnel 0 temporarily disabled due to recursive routing
Why is Tunnel 0 disabled?

Answer options

• A. Because dynamic routing is not enabled.
• B. Because the tunnel cannot reach its tunnel destination.
• C. Because the best path to the tunnel destination is through the tunnel itself.
• D. Because the router cannot recursively identify its egress forwarding interface.

Correct answer: C

Explanation

Tunnel 0 is disabled because the best route to reach the tunnel destination is through the tunnel itself, leading to a recursive routing issue. The other options do not accurately describe the problem; dynamic routing being disabled or the tunnel being unable to reach its destination are not the reasons for the recursive routing error.