What solution allows the network switch to automatically recover from such an issue?

While working in the core network building, a technician accidently bumps the fiber connection between two core switches and damages one of the pairs of fiber. As designed, the link was placed into a non-forwarding state due to a fault with UDLD. After the damaged cable was replaced, the link did not recover.

What solution allows the network switch to automatically recover from such an issue?
A . macros
B . errdisable autorecovery
C . IP Event Dampening
D . command aliases
E . Bidirectional Forwarding Detection

View Answer

Answer: B

Explanation:

There are a number of events which can disable a link on a Catalyst switch, such as the detection of a loopback, UDLD failure, or a broadcast storm. By default, manual intervention by an administrator is necessary to restore the interface to working order; this can be done by issuing shutdown followed by no shutdown on the interface. The idea behind requiring administrative action is so that a human engineer can intercede, assess, and (ideally) correct the issue.

However, some configurations may be prone to accidental violations, and a steady recurrence of these can amount to a huge time sink for the administrative staff. This is where errdisable autorecovery can be of great assistance. We can configure the switch to automatically re-enable any error-disabled interfaces after a specified timeout period. This gives the offending issue a chance to be cleared by the user (for example, by removing an unapproved device) without the need for administrative intervention. Reference: http://packetlife.net/blog/2009/sep/14/errdisable-autorecovery/