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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
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Chapter 25 Configuring UDLD Configuring UDLD
Enabling UDLD Globally
Beginning in privileged EXEC mode, follow these steps to enable UDLD in the aggressive or normal
mode and to set the configurable message timer on all fiber-optic ports on the switch:
To disable UDLD globally, use the no udld enable global configuration command to disable normal
mode UDLD on all fiber-optic ports. Use the no udld aggressive global configuration command to
disable aggressive mode UDLD on all fiber-optic ports.
Enabling UDLD on an Interface
Beginning in privileged EXEC mode, follow these steps either to enable UDLD in the aggressive or
normal mode or to disable UDLD on a port:
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 udld {aggressive | enable | message time
message-timer-interval}Specify the UDLD mode of operation:
• aggressive—Enables UDLD in aggressive mode on all fiber-optic
ports.
• enable—Enables UDLD in normal mode on all fiber-optic ports on
the switch. UDLD is disabled by default.
An individual interface configuration overrides the setting of the
udld enable global configuration command.
For more information about aggressive and normal modes, see the
“Modes of Operation” section on page 25-1.
• message time message-timer-interval—Configures the period of
time between UDLD probe messages on ports that are in the
advertisement phase and are detected to be bidirectional. The range
is from 7 to 90 seconds.
Note This command affects fiber-optic ports only. Use the udld
interface configuration command to enable UDLD on other port
types. For more information, see the “Enabling UDLD on an
Interface” section on page 25-5.
Step 3 end Return to privileged EXEC mode.
Step 4 show udld Verify your entries.
Step 5 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Specify the port to be enabled for UDLD, and enter interface
configuration mode.
Step 3 no shutdown Enable the port, if necessary. By default, user network interfaces
(UNIs) and enhanced network interfaces (ENIs) are disabled, and
network node interfaces (NNIs) are enabled.