Configuring Udld; Default Udld Configuration; Enabling Udld Globally - Cisco Catalyst 2950 Software Configuration Manual

Chapter 18

Configuring UDLD

Configuring UDLD
This section describes how to configure UDLD on your switch. It contains this configuration
information:
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Default UDLD Configuration

Table 18-1
Table 18-1 Default UDLD Configuration
Feature
UDLD global enable state
UDLD per-interface enable state for fiber-optic media
UDLD per-interface enable state for twisted-pair (copper)
media
A UDLD-capable interface also cannot detect a unidirectional link if it is connected to a
UDLD-incapable port of another switch.

Enabling UDLD Globally

Beginning in privileged EXEC mode, follow these steps to enable UDLD globally on all fiber-optic
interfaces on the switch:
Command
Step 1 configure terminal
Step 2
udld enable
Step 3
end
Step 4 show udld
Step 5
copy running-config startup-config
78-11380-04
Default UDLD Configuration, page 18-3
Enabling UDLD Globally, page 18-3
Enabling UDLD on an Interface, page 18-4
Resetting an Interface Shut Down by UDLD, page 18-4
shows the default UDLD configuration.
Default Setting
Globally disabled
Disabled on all Ethernet fiber-optic interfaces
Disabled on all Ethernet 10/100 and 1000BASE-TX
interfaces
Purpose
Enter global configuration mode.
Enable UDLD on all fiber-optic interfaces on the switch. UDLD is
disabled by default.
This command affects fiber-optic interfaces only. Use the udld interface
configuration command to enable UDLD on other interface types. For
more information, see the "Enabling UDLD on an Interface" section on
page 18-4.
An individual interface configuration overrides the setting of the udld
enable global configuration command.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Catalyst 2950 Desktop Switch Software Configuration Guide
Configuring UDLD
18-3