cdp

To enable the Cisco Discovery Protocol (CDP) and configure CDP attributes, use the cdp command. To disable CDP or reset CDP attributes, use the no form of this command.

cdp { advertise { v1 | v2 } | enable | format device-id { mac-address | serial-number | system-name } | holdtime seconds | timer seconds }

no cdp { advertise | enable | format device-id { mac-address | serial-number | system-name } | holdtime seconds | timer seconds }

Syntax Description

advertise { v1 | v2 }
Configures the version to use to send CDP advertisements. Version-2 is the default state.
enable
Enables CDP for all Ethernet interfaces.
format device-id
Configures the format of the CDP device ID.
mac-address
Uses the MAC address as the CDP device ID.
serial-number
Uses the serial number as the CDP device ID.
system-name
Uses the system name, which can be expressed as a fully qualified domain name, as the CDP device ID. This is the default.
holdtime seconds
Specifies the amount of time a receiver should hold CDP information before discarding it. The range is from 10 to 255 seconds; the default is 180 seconds.
timer seconds
Sets the transmission frequency of CDP updates in seconds. The range is from 5 to 254; the default is 60 seconds.

Command Default

None

Command Modes

Global configuration mode

Command History

Release
Modification
4.0(0)N1(1a)
This command was introduced.

Examples

This example shows how to enable CDP on all Ethernet interfaces:

switch# configure terminal
switch(config)# cdp enable
 

This example shows how to configure the MAC address as the CDP device ID:

switch# configure terminal
switch(config)# cdp format device-id mac-address
 

This example shows how to disable CDP on all Ethernet interfaces:

switch# configure terminal
switch(config)# no cdp enable

Related Commands

Command
Description
show cdp
Displays Cisco Discovery Protocol (CDP) information.