Command Reference Guide

UniDirectional Link Detection Commands
CLI Command Reference
September 2014 Page 490
HP Moonshot Switch Module CLI Command Reference
UniDirectional Link Detection Commands
The purpose of the UniDirectional Link Detection (UDLD) feature is to detect and avoid unidirectional links. A
unidirectional link is a forwarding anomaly in a Layer 2 communication channel in which a bi-directional link
stops passing traffic in one direction. Use the UDLD commands to detect unidirectional links’ physical ports.
UDLD must be enabled on both sides of the link in order to detect a unidirectional link. The UDLD protocol
operates by exchanging packets containing information about neighboring devices.
udld enable (Global Config)
This command enables UDLD globally on the switch.
no udld enable (Global Config)
This command disables udld globally on the switch.
udld message time
This command configures the interval between UDLD probe messages on ports that are in the advertisement
phase. The range is from 7 to 90 seconds.
udld timeout interval
This command configures the time interval after which UDLD link is considered to be unidirectional. The range
is from 5 to 60 seconds.
Default disable
Format
udld enable
Mode Global Config
Format
no udld enable
Mode Global Config
Default 15 seconds
Format
udld message time interval
Mode Global Config
Default 5 seconds
Format
udld timeout interval interval
Mode Global Config