Cisco Cisco Gigabit Ethernet Switch Module (CGESM) for HP Technical References

Use the show udld user EXEC command to display UniDirectional Link Detection (UDLD) 
administrative and operational status for all ports or the specified port.

show udld [interface-id] [ | {begin | exclude | include} expression]

User EXEC

If you do not enter an interface-id, administrative and operational UDLD status for all interfaces appear.

Expressions are case sensitive. For example, if you enter | exclude output, the lines that contain output 
do not appear, but the lines that contain Output appear.

This is an example of output from the show udld interface-id command. For this display, UDLD is 
enabled on both ends of the link, and UDLD detects that the link is bidirectional. 

 describes 

the fields in this display.

Switch> show udld gigabitethernet0/1

Interface gi0/1

---

Port enable administrative configuration setting: Follows device default

Port enable operational state: Enabled

Current bidirectional state: Bidirectional

Current operational state: Advertisement - Single Neighbor detected

Message interval: 60

Time out interval: 5

    Entry 1

    Expiration time: 146

    Device ID: 1

    Current neighbor state: Bidirectional

    Device name: Switch-A 

    Port ID: Gi0/1

    Neighbor echo 1 device: Switch-B

    Neighbor echo 1 port: Gi0/2 

    Message interval: 5

    CDP Device name: Switch-A

(Optional) ID of the interface and port number. Valid interfaces include 
physical ports and VLANs. The VLAN range is 1 to 4094.

(Optional) Display begins with the line that matches the expression.

(Optional) Display excludes lines that match the expression.

(Optional) Display includes lines that match the specified expression.

Expression in the output to use as a reference point.

12.2(25)SE1

This command was introduced.