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Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter26 Configuring CDP
Configuring CDP
Configuring the CDP Characteristics
You can configure the frequency of CDP updates, the amount of time to hold the information before
discarding it, and whether or not to send Version-2 advertisements.
Beginning in privileged EXEC mode, follow these steps to configure the CDP timer, holdtime, and
advertisement type.
Note Steps 2 through 4 are all optional and can be performed in any order.
Use the no form of the CDP commands to return to the default settings.
This example shows how to configure CDP characteristics.
Switch# configure terminal
Switch(config)# cdp timer 50
Switch(config)# cdp holdtime 120
Switch(config)# cdp advertise-v2
Switch(config)# end
For additional CDP show commands, see the “Monitoring and Maintaining CDP” section on page26-5.
Disabling and Enabling CDP
CDP is enabled by default.
Note Switch clusters and other Cisco devices (such as Cisco IP Phones) regularly exchange CDP messages.
Disabling CDP can interrupt cluster discovery and device connectivity. For more information, see
Chapter 6, “Clustering Switches” and see Getting Started with Cisco Network Assistant, available on
Cisco.com.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 cdp timer seconds (Optional) Set the transmission frequency of CDP updates in seconds.
The range is 5 to 254; the default is 60 seconds.
Step3 cdp holdtime seconds (Optional) Specify the amount of time a receiving device should hold the
information sent by your device before discarding it.
The range is 10 to 255 seconds; the default is 180 seconds.
Step4 cdp advertise-v2 (Optional) Configure CDP to send Version-2 advertisements.
This is the default state.
Step5 end Return to privileged EXEC mode.
Step6 show cdp Verify your settings.
Step7 copy running-config startup-config (Optional) Save your entries in the configuration file.