Shutdown prevention for loop-detection on an interface

The shutdown prevention for loop-detection functionality allows users to disable the shutdown of a port when the loop detection probe packet is received on an interface.

The shutdown prevention provides control over deciding which port is allowed to enter into an error-disabled state and go into a shutdown state when a loop is detected. This function can also be used as a test tool to detect Layer 2 and Layer 3 loops in network current data packet flow.

Shutdown prevention for loop-detection does not allow any corrective action to be taken on the loop. There could be network instability due to the presence of network loops, if adequate corrective measures are not taken by the network administrator.

To enable shutdown prevention for loop detection, follow these steps.

  1. Enter global configuration mode.
    device# configure terminal
  2. Specify the interface on which you would like to enable the loop-detection shutdown-disable command.
    device(config)# interface ethernet 1/1/7
  3. Enable shutdown prevention for loop detection on Ethernet interface 1/1/7.
    device(config-if-e1000-1/1/7)# loop-detection shutdown-disable