Configuring uni-directional link detection (UDLD) (CLI)

For detailed information about UDLD, see Uni-directional link detection (UDLD).


[no] interface <port-list> link-keepalive

Enables UDLD on a port or range of ports.

To disable this feature, enter the no form of the command.

Default: UDLD disabled


link-keepalive interval <interval>

Determines the time interval to send UDLD control packets. The interval parameter specifies how often the ports send a UDLD packet. You can specify from 10 to 100, in 100-ms increments, where 10 is 1 second, 11 is 1.1 seconds, and so on.

Default: 50 (5 seconds)


link-keepalive retries <num>

Determines the maximum number of retries to send UDLD control packets. The num parameter specifies the maximum number of times the port will try the health check. You can specify a value from 3 to 10.

Default: 5


[no] interface <port-list> link-keepalive vlan <vid>

Assigns a VLAN ID to a UDLD-enabled port for sending tagged UDLD control packets.Under default settings, untagged UDLD packets can still be transmitted and received on tagged only ports; however, a warning message is logged.

The no form of the command disables UDLD on the specified ports.

Default: UDLD packets are untagged; tagged-only ports transmit and receive untagged UDLD control packets