Default Udld Configuration; Configuration Guidelines - Cisco Catalyst 2975 Software Configuration Manual

Configuring UDLD

Default UDLD Configuration

Table 26-1
Table 26-1 Default UDLD Configuration
Feature
UDLD global enable state
UDLD per-port enable state for fiber-optic media
UDLD per-port enable state for twisted-pair (copper) media
UDLD aggressive mode

Configuration Guidelines

These are the UDLD configuration guidelines:
•
•
•
Loop guard works only on point-to-point links. We recommend that each end of the link has a directly
Caution
connected device that is running STP.
Catalyst 2975 Switch Software Configuration Guide
26-4
shows the default UDLD configuration.
UDLD is not supported on ATM ports.
A UDLD-capable port cannot detect a unidirectional link if it is connected to a UDLD-incapable
port of another switch.
When configuring the mode (normal or aggressive), make sure that the same mode is configured on
both sides of the link.
Default Setting
Globally disabled
Disabled on all Ethernet fiber-optic ports
Disabled on all Ethernet 10/100 and 1000BASE-TX ports
Disabled
Chapter 26 Configuring UDLD
OL-19720-02