CDP Commands on Cisco IOS XR Software
This chapter describes the Cisco IOS XR software commands for monitoring the networking device and network using Cisco Discovery Protocol (CDP).
For detailed information about CDP concepts, configuration tasks, and examples, refer to the Implementing CDP on Cisco IOS XR Software module in Cisco IOS XR System Management Configuration Guide.
cdp
To enable the Cisco Discovery Protocol (CDP) globally or on a interface, use the cdp command in the appropriate configuration mode. To disable CDP globally or on an interface, use the no form of this command.
cdp
no cdp
Syntax Description
This command has no arguments or keywords.
Defaults
CDP is disabled.
Command Modes
Global configuration
Interface configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. The enable and disable keywords were removed. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
By default, CDP is disabled globally. To enable CDP, CDP must be enabled globally and then enabled for each interface.
To enable CDP globally, use the cdp command in global configuration mode. To disable CDP globally, use the no form of this command in global configuration mode.
To enable CDP on a specific interface, use the cdp command in interface configuration mode. To disable CDP on a specific interface, use the no form of this command in interface configuration mode.
The following interface types do not support CDP:
•802.1Q VLAN subinterfaces
•ATM interfaces and ATM subinterfaces
•Bundle Interfaces
•Loopback interfaces
•Service interfaces
•Tunnel Interfaces
Examples
The following example shows how to globally enable CDP:
RP/0/RP0/CPU0:router(config)# cdp
The following example shows how to enable CDP on Packet-over-SONET/SDH (POS) interface 0/0/0/1:
RP/0/RP0/CPU0:router(config)# interface POS 0/0/0/1
RP/0/RP0/CPU0:router(config-if)# cdp
The following example shows how to disable CDP on Packet-over-SONET/SDH (POS) interface 0/0/0/1:
RP/0/RP0/CPU0:router(config)# interface POS 0/0/0/1
RP/0/RP0/CPU0:router(config-if)# no cdp
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
cdp advertise v1
To change the version of Cisco Discovery Protocol (CDP) that is used to communicate with neighboring devices to version 1 (CDPv1), use the cdp advertise v1 command in global configuration mode. To remove the cdp advertise v1 command from the configuration file and restore the system to its default condition with respect to this command, use the no form of this command.
cdp advertise v1
no cdp advertise [v1]
Syntax Description
This command has no arguments or keywords.
Defaults
Version 2 is enabled.
Command Modes
Global configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
The v2 keyword was removed. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
CDPv2 packets are sent by default. CDP also sends and receives CDPv1 packets if the device with which CDP is interacting does not process CDPv2 packets.
CDPv2 adds device information over CDPv1. The additional information that is contained in the CDPv2 messages relates to Native VLAN, VLAN Trunking Protocol (VTP) Management Domain, Ethernet Duplex, and other features.
Examples
The following example shows how to set a networking device to send and receive only CDPv1 advertisements:
RP/0/RP0/CPU0:router(config)# cdp advertise v1
The following example shows how to restore the default condition (sending and receiving CDPv2 advertisements):
RP/0/RP0/CPU0:router(config)# no cdp advertise
Related Commands
|
|
cdp |
Enables CDP on a supported interface. |
show cdp |
Displays global CDP information, including timer and holdtime information. |
cdp holdtime
To specify the time for which the receiving device should hold a Cisco Discovery Protocol (CDP) packet from your networking device before discarding it, use the cdp holdtime command in global configuration mode. To remove the cdp holdtime global configuration command from the configuration file and restore the system to its default condition with respect to this command, use the no form of this command.
cdp holdtime seconds
no cdp holdtime
Syntax Description
seconds |
Holdtime to be sent in the CDP update packets. Range is 10 seconds to 255 seconds. |
Defaults
seconds: 180
Command Modes
Global configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
CDP packets are sent with a time-to-live value, or holdtime, that is nonzero after an interface is enabled.
The CDP holdtime must be set to a higher number of seconds than the time between CDP transmissions, which is set using the cdp timer command.
Examples
The following example shows how to specify that the CDP packets sent from the networking device are held by the receiving device for 60 seconds before being discarded. You might want to set the holdtime lower than the default setting of 180 seconds if information about your networking device changes often and you want the receiving devices to purge this information more quickly.
RP/0/RP0/CPU0:router(config)# cdp holdtime 60
The following example shows how to use the no form of the command to set the holdtime to the default of 180 seconds:
RP/0/RP0/CPU0:router(config)# no cdp holdtime
Related Commands
|
|
cdp timer |
Specifies how often the software sends CDP updates. |
show cdp |
Displays global CDP information, including timer and holdtime information. |
cdp log adjacency changes
To log changes to the Cisco Discovery Protocol (CDP) adjacency table, use the cdp log adjacency changes command in global configuration mode. To disable the logging, use the no form of this command.
cdp log adjacency changes
no cdp log adjacency changes
Syntax Description
This command has no arguments or keywords.
Defaults
CDP adjacency table logging is disabled.
Command Modes
Global configuration
Command History
|
|
Release 3.3.0 |
This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
When CDP adjacency table logging is enabled, a syslog is generated each time a CDP neighbor is added or removed.
Examples
The following example shows how to enable CDP adjacency table logging:
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# cdp log adjacency changes
When CDP adjacency table logging is enabled, a syslog is generated each time a CDP neighbor is added or removed. The following is an example of the log entry:
LC/0/5/CPU0:Jun 5 10:51:18.081 : cdp[109]: %L2-CDP-6-DELETED_NEIGHBOR :
CDP Neighbour TBA04110127 on interface GigabitEthernet0/5/0/0 has been deleted, remote
interface 3/2
LC/0/5/CPU0:Jun 5 10:51:33.120 : cdp[109]: %L2-CDP-6-NEW_NEIGHBOR : New CDP neighbor
TBA04110127 detected on interface GigabitEthernet0/5/0/0, remote interface 3/2
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
cdp timer
To specify how often the software sends Cisco Discovery Protocol (CDP) updates, use the cdp timer command in global configuration mode. To remove the cdp timer global configuration command from the configuration file and restore the system to its default condition with respect to this command, use the no form of this command.
cdp timer seconds
no cdp timer
Syntax Description
seconds |
Frequency with which the Cisco IOS XR software sends CDP updates. Range is 5 to 254 seconds. The default is 60 seconds. |
Defaults
seconds: 60 seconds
Command Modes
Global configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
A lower timer setting causes CDP updates to be sent more frequently.
Examples
The following example shows how to set the CDP timer to 80 seconds, which is less frequent than the default setting of 60 seconds:
RP/0/RP0/CPU0:router(config)# cdp timer 80
Related Commands
|
|
cdp holdtime |
Specifies the time for which the receiving device should hold a CDP packet sent by your networking device before discarding it. |
show cdp |
Displays global CDP information, including timer and holdtime information. |
clear cdp counters
To reset Cisco Discovery Protocol (CDP) traffic counters to zero (0), use the clear cdp counters command in EXEC mode.
clear cdp counters location node-id
Syntax Description
location node-id |
Clears CDP traffic counters for the designated node. The node-id argument is entered in the rack/slot/module notation. |
Defaults
The counters are set to zero.
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Examples
The following example shows how to clear CDP counters. The show cdp traffic output shows that all traffic counters have been reset to zero (0).
RP/0/RP0/CPU0:router# clear cdp counters
RP/0/RP0/CPU0:router# show cdp traffic
Packets output: 0, Input: 0
Hdr syntax: 0, Chksum error: 0, Encaps failed: 0
No memory: 0, Invalid packet: 0, Truncated: 0
CDP version 1 advertisements output: 0, Input: 0
CDP version 2 advertisements output: 0, Input: 0
Unrecognize Hdr version: 0, File open failed: 0
Related Commands
|
|
clear cdp table |
Clears and resizes the table that contains CDP information about neighbors. |
show cdp traffic |
Displays traffic information between devices gathered using CDP. |
clear cdp table
To clear and automatically resize the table that contains Cisco Discovery Protocol (CDP) information about neighbors, use the clear cdp table command in EXEC mode.
clear cdp table location node-id
Syntax Description
location node-id |
Clears and resizes the CDP table for the designated node. The node-id argument is entered in the rack/slot/module notation. |
Defaults
No default behavior or values
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Use the clear cdp table command to clear and resize the CDP table that contains the neighbor entries. The new table size is calculated according to the recommended hash table size, as seen in the show cdp command output.
Examples
The following example shows how to clears and resize the CDP table. The output of the show cdp neighbors command before and after use of the clear cdp table command shows that all information has been deleted from the table:
RP/0/RP0/CPU0:router# show cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
TBA04341195(15la Mg0/RP1/CPU0/0 171 T S WS-C2924 0/1
RP/0/RP0/CPU0:router# clear cdp table
RP/0/RP0/CPU0:router# show cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
The show cdp command shows that the table has been resized:
RP/0/RP0/CPU0:router# show cdp
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
show cdp neighbors |
Displays information about neighboring devices discovered by CDP. |
show cdp
To display global Cisco Discovery Protocol (CDP) information, including CDP version, timer, and holdtime information, use the show cdp command in EXEC mode.
show cdp
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Use the show cdp command to display CDP version, timer, and holdtime information relative to CDP operations.
Examples
The following example shows how to use the show cdp command to verify the CDP global settings:
RP/0/0/CPU0:router# show cdp
Sending CDP packets every 20 seconds
Sending a holdtime value of 30 seconds
Sending CDPv2 advertisements is not enabled
Table 8 describes the significant fields shown in the display.
Table 8 show cdp Field Descriptions
|
|
Sending CDP packets every 20 seconds |
Interval between transmissions of CDP advertisements. This field is controlled by the cdp timer command. |
Sending a holdtime value of 30 seconds |
Time for which the device directs the neighbor to hold a CDP advertisement before discarding it. This field is controlled by the cdp holdtime command. |
Sending CDPv2 advertisements is not enabled |
State of being enabled or disabled for the transmission of CDP version 2-type advertisements. This field is controlled by the cdp advertise v1 command. |
Related Commands
|
|
cdp advertise v1 |
Changes the version of CDP that is used to communicate with neighboring devices to CDPv1. |
cdp holdtime |
Specifies the time for which the receiving device should hold a CDP packet sent by your networking device before discarding it. |
cdp timer |
Specifies how often the software sends CDP updates. |
clear cdp table |
Clears and resizes the table that contains CDP information about neighbors. |
show cdp entry |
Displays information about a specific neighboring device or all neighboring devices discovered using CDP. |
show cdp interface |
Displays information about the interfaces on which CDP is enabled. |
show cdp neighbors |
Displays information about neighboring devices discovered by CDP. |
show cdp traffic |
Displays traffic information between devices gathered using CDP. |
show cdp entry
To display information about a specific neighboring device or all neighboring devices discovered using Cisco Discovery Protocol (CDP), use the show cdp entry command in EXEC mode.
show cdp entry {* | entry-name} [protocol | version]
Syntax Description
* |
Displays all CDP neighbors. |
entry-name |
Name of a neighbor about which you want information. |
protocol |
(Optional) Displays protocol information associated with CDP neighbor entries. |
version |
(Optional) Displays version information associated with CDP neighbor entries. |
Defaults
This command displays information about a particular device that has been discovered by CDP.
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Examples
The following is sample output from the show cdp entry command. Information about device ID, address, platform, interface, holdtime, and version is displayed.
RP/0/RP0/CPU0:router# show cdp entry TBA04341195
-------------------------
Device ID: TBA04341195(sys-235)
Platform: WS-C6006, Capabilities: Trans-Bridge Switch
Interface: MgmtEth0/RP1/CPU0/0
Port ID (outgoing port): 4/18
WS-C6006 Software, Version McpSW: 7.2(2) NmpSW: 7.2(2)
Copyright (c) 1995-2002 by Cisco Systems
VTP Management Domain: 'sys'
Table 9 describes the significant fields shown in the display.
Table 9 show cdp entry Field Descriptions
|
|
Device ID |
ID code assigned during installation of the router. |
Entry address(es) |
Addresses of the platform, selected interface, and port ID. |
Platform |
Platform name. |
Capabilities |
Special functions that the platform can perform (in this case the platform is a trans-bridge switch). |
Interface |
Interface location expressed as rack/slot/module/port. |
Port ID (outgoing port) |
Location of the port in use by the interface. |
Holdtime |
Time (in seconds) for which the device directs the neighbor to hold a CDP advertisement before discarding it. This field is controlled by the cdp holdtime command. |
Version |
Software version. |
advertisement version |
Version number of the advertising protocol. |
VTP Management Domain |
VLAN Trunking Protocol (VTP) domain name of neighbor device. |
Native VLAN |
VLAN ID. |
Duplex |
Duplex setting: half or full. |
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
show cdp interface |
Displays information about the interfaces on which CDP is enabled. |
show cdp neighbors |
Displays information about neighboring devices discovered by CDP. |
show cdp traffic |
Displays traffic information between devices gathered using CDP. |
show cdp interface
To display information about the interfaces on which Cisco Discovery Protocol (CDP) is enabled, use the show cdp interface command in EXEC mode.
show cdp interface [type interface-path-id | location node-id]
Syntax Description
type |
Interface type. For more information, use the question mark (?) online help function. |
interface-path-id |
Physical interface or virtual interface. Note Use the show interfaces command to see a list of all interfaces currently configured on the router. For more information about the syntax for the router, use the question mark (?) online help function. |
location node-id |
(Optional) Displays detailed CDP information for the designated node. The node-id argument is entered in the rack/slot/module notation. |
Defaults
This command displays information about the interfaces on which CDP has been enabled.
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Use the show cdp interface command to display information about any CDP interfaces. When an interface is specified in the command syntax, information is displayed about the specific interface. Not specifying the interface displays information about all interfaces.
Examples
The following is sample output from the show cdp interface command. Information about the status, CDP timer, and holdtime settings is displayed for all interfaces on which CDP is enabled.
RP/0/RP0/CPU0:router# show cdp interface
Sending CDP packets every 120 seconds
Sending CDP packets every 120 seconds
Sending CDP packets every 120 seconds
Sending CDP packets every 120 seconds
MgmtEth0/RP1/CPU0/0 is Up
Sending CDP packets every 120 seconds
The following is sample output from the show cdp interface command with an interface specified. Information about the status, CDP timer, and holdtime settings is displayed for Packet-over-SONET/SDH (POS) interface 0/2/0/1 only.
RP/0/RP0/CPU0:router# show cdp interface POS 0/2/0/1
Sending CDP packets every 60 seconds
Table 10 describes the significant fields shown in the display.
Table 10 show cdp interface Field Descriptions
|
|
POS0/2/0/1 is Up |
Current condition of POS interface 0/0/2/1. |
Encapsulation HDLC |
Interface is encoding packets using the Cisco HDLC Layer 2 encapsulation. |
Sending CDP packets every 60 seconds |
Interval between transmissions of CDP advertisements. This field is controlled by the cdp timer command. |
Holdtime is 180 seconds |
Time for which the device directs the neighbor to hold a CDP advertisement before discarding it. This field is controlled by the cdp holdtime command. |
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
show cdp entry |
Displays information about a specific neighboring device or all neighboring devices discovered using CDP. |
show cdp neighbors |
Displays information about neighboring devices discovered by CDP |
show cdp traffic |
Displays traffic information between devices gathered using CDP. |
show cdp neighbors
To display detailed information about neighboring devices discovered using Cisco Discovery Protocol (CDP), use the show cdp neighbors command in EXEC mode.
show cdp neighbors [type interface-path-id | location node-id] [detail]
Syntax Description
type |
Interface type. For more information, use the question mark (?) online help function. |
interface-path-id |
Physical interface or virtual interface. Note Use the show interfaces command to see a list of all interfaces currently configured on the router. For more information about the syntax for the router, use the question mark (?) online help function. |
location node-id |
(Optional) Displays detailed CDP information for the designated node. The node-id argument is entered in the rack/slot/module notation. |
detail |
(Optional) Displays detailed information about a neighbor or neighbors, including network address, enabled protocols, holdtime, and software version. The output includes information about both IPv4 and IPv6 addresses. |
Defaults
No default behavior or values
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. When used with the detail keyword, the output was modified to display IPv6 neighbors. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Use the show cdp neighbors command to display information about any CDP neighbors. When a location is specified in the command syntax, information about the neighbor is displayed for the specified node. Not specifying the location displays information about the neighbor for all interfaces.
Use the show cdp neighbors command with the detail keyword to display additional information, including IPv6 neighbors.
Examples
The following is sample output from the show cdp neighbors command:
RP/0/RP0/CPU0:router# show cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater
Device ID Local Intrfce Holdtme Capability Platform Port ID
cisco_1 Mg0/0/CPU0/0 139 T S WS-C2924M Fa0/6
cisco_2 PO0/3/0/0 173 R CRS-1 PO0/3/0/0
TBA04110127 Gi0/7/0/0 173 T S WS-C6506 3/9
cisco_3 Gi0/7/0/2 171 R CRS-1 Gi0/4/0/2
Table 11 describes the significant fields shown in the display.
Table 11 show cdp neighbors Field Descriptions
|
|
Capability Codes |
Type of device that can be discovered. |
Device ID |
Name of the neighbor device. |
Local Intrfce |
Protocol being used by the connectivity media and the interface number. |
Holdtme |
Remaining time, in seconds, for which the current device holds the CDP advertisement from a sending router before discarding it. |
Capability |
Type of the device listed in the CDP Neighbors table. Values are as follows: •R—Router •T—Transparent bridge •B—Source-routing bridge •S—Switch •H—Host •I—Internet Group Management Protocol (IGMP) device •r—Repeater |
Platform |
Product number of the device. |
Port ID |
Protocol and port number of the device. |
The following is sample output for IPv4 and IPv6 neighbors from the show cdp neighbors detail command:
RP/0/0/CPU0:router# show cdp neighbor detail
-------------------------
Platform: cisco 12008/GRP, Capabilities: Router
Port ID (outgoing port): POS0/2/0/3
Cisco IOS XR Software, Version 0.0.0[Default]
Copyright (c) 2005 by cisco Systems, Inc.
Table 12 describes the significant fields shown in the display.
Table 12 show cdp neighbors detail Field Descriptions
|
|
Device ID |
Name of the neighbor device. |
Entry address(es) |
List of network addresses of neighbor devices. The address can be in IP, or Connectionless Network Service (CLNS) protocol conventions. |
Platform |
Product name and number of the neighbor device. |
Capabilities |
Device type of the neighbor. This device can be a router, a bridge, a transparent bridge, a source-routing bridge, a switch, a host, an IGMP device, or a repeater. |
Interface |
Interface being used by the connectivity medium. |
Port ID |
Port number of the port on the current device. |
Holdtime |
Remaining time (in seconds) for which the current device holds the CDP advertisement from a sending router before discarding it. |
Version |
Software version of the neighbor device. |
advertisement version |
Version number of the advertising protocol. |
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
show cdp entry |
Displays information about a specific neighboring device or all neighboring devices discovered using CDP. |
show cdp interface |
Displays information about the interfaces on which CDP is enabled. |
show cdp traffic |
Displays traffic information between devices gathered using CDP. |
show cdp traffic
To display information about the traffic gathered between devices using Cisco Discovery Protocol (CDP), use the show cdp traffic command in EXEC mode.
show cdp traffic [location node-id]
Syntax Description
location node-id |
(Optional) Displays CDP information for the CDP packets sent and received on the designated node only. The node-id argument is entered in the rack/slot/module notation. |
Defaults
Displays CDP information aggregated across all nodes.
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Examples
The following is sample output from the show cdp traffic command:
RP/0/RP0/CPU0:router# show cdp traffic
Packets output: 50662, Input: 40414
Hdr syntax: 0, Chksum error: 0, Encaps failed: 0
No memory: 0, Invalid packet: 0, Truncated: 0
CDP version 1 advertisements output: 0, Input: 0
CDP version 2 advertisements output: 50662, Input: 40414
Unrecognize Hdr version: 0, File open failed: 0
Table 13 describes the significant fields shown in the display.
Table 13 show cdp traffic Field Descriptions
|
|
Packets output |
Number of CDP advertisements sent by the local device. Note that this value is the sum of the CDP version 1 advertisements output field and the CDP version 2 advertisements output field. |
Input |
Number of CDP advertisements received by the local device. Note that this value is the sum of the CDP version 1 advertisements input field and the CDP version 2 advertisements input field. |
Hdr syntax |
Number of CDP advertisements having bad headers that have been received by the local device. |
Chksum error |
Number of times the checksum (verifying) operation failed on incoming CDP advertisements. |
Encaps failed |
Number of times CDP failed to send advertisements on an interface because of a failure caused by the bridge port of the local device. |
No memory |
Number of times that the local device did not have enough memory to store the CDP advertisements in the advertisement cache table when the device was attempting to assemble advertisement packets for transmission and parse them when receiving them. |
Invalid packet |
Number of invalid CDP advertisements received and sent by the local device. |
Truncated |
Number of times truncated CDP advertisements were sent because there was not enough space in the CDP packet to hold all CDP type-length-values (TLVs). |
CDP version 1 advertisements output |
Number of CDP version 1 advertisements sent by the local device. |
Input |
Number of CDP version 1 advertisements received by the local device. |
CDP version 2 advertisements output |
Number of CDP version 2 advertisements sent by the local device. |
Input |
Number of CDP version 2 advertisements received by the local device. |
Unrecognize Hdr version |
Number of packets received from a CDP version that was outside the current configuration. |
File open failed |
Number of times that CDP failed to connect to one of the underlying services it uses. |
Related Commands
|
|
show cdp |
Displays global CDP information, including timer and holdtime information. |
show cdp entry |
Displays information about a specific neighboring device or all neighboring devices discovered using CDP. |
show cdp interface |
Displays information about the interfaces on which CDP is enabled. |
show cdp neighbors |
Displays information about neighboring devices discovered by CDP. |