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CDP Commands
Cisco Discovery Protocol (CDP) is a proprietary protocol that discovers information
about neighboring devices by passing messages across the Data Link Layer. It is
used to share information about nearby network equipment. Participating devices
send CDP announcements from each connected network interface to the multicast
address 01-00-0C-CC-CC-CC. These packets may be received by any networking
devices that support CDP. By default, CDP announcements are sent every 60
seconds. Each device that supports CDP stores the information received from other
devices in a table that can be viewed using the
show cdp neighbors
command. This
information is refreshed each time an announcement is received, and the holdtime
for that entry is reinitialized.
The information contained in CDP announcements may include the CDP version,
host name, IP address and port identifier from which the announcement was sent,
device type, and other device specific information.
Table 110: CDP Commands
Command
Function
Mode
cdp
Enables CDP globally on the switch
GC
cdp hold-time
Specifies the amount of time the receiving device
should hold a CDP packet sent from this switch
GC
cdp transmit-interval
Specifies the periodic transmission interval for CDP
advertisements
GC
cdp version
Specifies the CDP version to use for transmitting
advertisements
GC
cdp
Enables CDP on the selected interface
IC
clear cdp table
Clears the CDP neighbor table
PE
show cdp
Shows global CDP configuration settings
PE
show cdp interface
Shows whether or not CDP is enabled on an
interface
PE
show cdp neighbors
Shows information about neighbors obtained by
monitoring CDP advertisements
PE
Summary of Contents for EX-3524
Page 2: ......
Page 28: ...Figures 28 ...
Page 34: ...Section I Getting Started 34 ...
Page 58: ...Chapter 1 Initial Switch Configuration Setting the System Clock 58 ...
Page 72: ...Chapter 2 Using the Command Line Interface CLI Command Groups 72 ...
Page 156: ...Chapter 5 SNMP Commands Notification Log Commands 156 ...
Page 164: ...Chapter 6 Remote Monitoring Commands 164 ...
Page 218: ...Chapter 7 Authentication Commands Management IP Filter 218 ...
Page 268: ...Chapter 8 General Security Measures Port based Traffic Segmentation 268 ...
Page 292: ...Chapter 9 Access Control Lists ACL Information 292 ...
Page 312: ...Chapter 10 Interface Commands Power Savings 312 ...
Page 324: ...Chapter 11 Link Aggregation Commands Trunk Status Display Commands 324 ...
Page 366: ...Chapter 15 Address Table Commands 366 ...
Page 428: ...Chapter 17 VLAN Commands Configuring Voice VLANs 428 ...
Page 572: ...Chapter 25 IP Interface Commands IPv6 Interface 572 ...
Page 578: ...Section I Appendices 578 ...