Fault Finder

Fault Finder is a feature that helps administrators to debug unusual network activity such as flapping links or transceivers or to troubleshoot issues such as multicast or broadcast storms. Fault Finder helps in preventing network loops and taking care of situations that arise out of defective equipment and malicious attacks.

The following is the list of issues detected by the Fault Finder:
  • Excessive CRC/alignment errors (bad cable)

  • Excessive flapping of transceivers (bad transceiver)

  • Too many undersized/giant packets (bad driver)

  • Excessive late collisions (cable too long)

  • High collision or drop rate (over bandwidth)

  • Excessive broadcast packets (broadcast storm)

  • Excessive multicast packets (multicast storm)

  • Duplex mismatch (duplex mismatch HDx - reconfigure to Full Duplex)

  • Duplex mismatch (duplex mismatch FDx - reconfigure port to Auto)

  • Rapid detection of link faults and recoveries (link flap)

  • Link loss detection (loss of link)


Fault finder is also known as FFI (find-fix-inform).