Udld (Interface Configuration Mode) - Cisco 4500M Command Reference Manual

udld (interface configuration mode)

udld (interface configuration mode)
To enable UDLD on an individual interface or to prevent a fiber interface from being enabled by the
(global configuration mode)
configuration mode)
form of this command.
Syntax Description
enable
aggressive
disable
Defaults
The fiber interfaces are enabled per the state of the global udld (enable or aggressive) command, and
the nonfiber interfaces are enabled with UDLD disabled.
Command Modes
Interface configuration
Command History Release
12.1(8a)EW
Usage Guidelines
If you enable aggressive mode, once all the neighbors of a port have aged out either in the advertisement
or in the detection phase, UDLD restarts the linkup sequence to try to resynchronize with any potentially
out-of-sync neighbor and shuts down the port if the message train from the link is still undetermined.
Use the no udld enable command on fiber ports to return control of UDLD to the global udld enable
command or to disable UDLD on nonfiber ports.
Use the udld aggressive command on fiber ports to override the setting of the global udld (enable or
aggressive) command. Use the no form on fiber ports to remove this setting, return control of UDLD enabling
back to the global udld command or to disable UDLD on nonfiber ports.
The disable keyword is supported on fiber ports only. Use the no form of this command to remove this
setting and return control of UDLD to the
If the port changes from fiber to nonfiber or vice versa, all configurations will be maintained because of
a change of module or a GBIC change detected by the platform software.
Examples
This example shows how to cause any port interface to enable UDLD, despite the current global
(global configuration mode)
Switch (config-if)# udld enable
Switch (config-if)#
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command setting, or if the port is a nonfiber port to disable UDLD, use the no
udld {enable | aggressive | disable }
no udld {enable | aggressive | disable}
Enables UDLD on this interface.
Enables UDLD in aggressive mode on this interface.
Disables UDLD on this interface.
Modification
Support for this command was introduced on the Catalyst 4500 series switch.
Chapter2 Cisco IOS Commands for the Catalyst 4500 Series Switches
command, use the udld command. To return to the
udld (global configuration mode)
setting:
udld
udld (global
command.
udld
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