Enabling Udld Globally - Cisco Catalyst 4500 Series Configuration Manual

Chapter 30 Configuring UDLD

Enabling UDLD Globally

To enable UDLD in aggressive or normal mode and to set the configurable message timer on all
fiber-optic interfaces on the switch, perform this task:
Command
Step 1
Switch# configure terminal
Step 2
Switch(config)# udld {aggressive | enable |
message time message-timer-interval} | fast-hello
error-reporting
Step 3
Switch(config)# end
Step 4
Switch# show udld
OL-25340-01
Purpose
Enters the global configuration mode.
Specifies UDLD and Fast UDLD operation:
• aggressive —Enables UDLD in aggressive mode on
all fiber-optic interfaces.
• enable —Enables UDLD in normal mode on all
fiber-optic interfaces 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
page 30-3.
• message time —message-timer-interval—
Configures the period of time between UDLD probe
messages on ports that are in the advertisement phase
and are determined to be bidirectional. The range is
from 1 to 90 seconds.
Prior to Cisco IOS Release 12.2(31)SGA, the
Note
timer range is 7 to 90 seconds. With
Cisco IOS Release 12.2(31)SGA, the timer range
is 1 to 90 seconds.
• fast-hello error reporting—If configured, Fast
UDLD does not errdisable a unidirectional link.
Instead, a log message informing link failure is
displayed on the console (behavior for fast UDLD
only).
Returns to privileged EXEC mode.
Verifies the configuration.
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
Configuring UDLD on the Switch
"Operation Modes" section on
30-5