Table Of Contents

CDP Debug Commands on Cisco IOS XR Software

debug cdp adjacency

debug cdp packets

CDP Debug Commands on Cisco IOS XR Software

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This chapter describes the commands used to debug Cisco Discovery Protocol Adjacency (CDP) on Cisco IOS XR software.

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Caution Because debugging output is assigned high priority in the CPU process, it can render the system unusable. For this reason, use debug commands only to troubleshoot specific problems or during troubleshooting sessions with Cisco technical support staff. Moreover, it is best to use debug commands during periods of lower network traffic and fewer users. Debugging during these periods decreases the likelihood that increased debug command processing overhead will affect system use.

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debug cdp adjacency

To enable debugging output for neighbor entry updates that are processed by Cisco Discovery Protocol (CDP), use the debug cdp adjacency command in EXEC mode. To turn off the debugging output, use the no form of this command.

debug cdp adjacency [location node-id | interface type instance]

no debug cdp adjacency [location node-id | interface type instance]

Syntax Description

location node-id	(Optional) Displays CDP debug information for a specified location. The node-id argument is entered in the rack/slot/module notation.
interface	(Optional) Displays CDP debug information for a specified interface.
type	(Optional) Interface type. For more information, use the question mark (?) online help function.
instance	(Optional) Either a physical interface instance or a virtual interface instance as follows: •Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation. –rack: Chassis number of the rack. –slot: Physical slot number of the modular services card or line card. –module: Module number. A physical layer interface module (PLIM) is always 0. –port: Physical port number of the interface. Note In references to a Management Ethernet interface located on a route processor card, the physical slot number is alphanumeric (RP0 or RP1) and the module is CPU0. Example: interface MgmtEth0/RP1/CPU0/0. •Virtual interface instance. Number range varies depending on interface type. For more information about the syntax for the router, use the question mark (?) online help function.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was 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.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Debugging output is assigned high priority in the CPU process and, therefore, can affect system performance. For more information about the impact on system performance when using debug commands, refer to Using Debug Commands on Cisco IOS XR Software.

This command shows when an entry is added to or removed from the neighbor cache. When an interface is specified in the command syntax, debugging is turned on for the specified interface. Not specifying the interface turns on debugging for all interfaces.

Task ID

Task ID	Operations
cdp	read

Examples

The following example shows how to enable debugging output for neighbor entry updates that are processed by CDP:

RP/0/RP0/CPU0:router# debug cdp adjacency

debug cdp packets

To enable debugging output for packet information processed by Cisco Discovery Protocol (CDP), use the debug cdp packets command in EXEC mode. To turn off the debugging output, use the no form of this command.

debug cdp packets [location node-id | interface type instance]

no debug cdp packets [location node-id | interface type instance]

Syntax Description

location node-id	(Optional) Displays CDP debug information for a specified location. The node-id argument is entered in the rack/slot/module notation.
interface	(Optional) Displays CDP debug information for a specified interface.
type	(Optional) Interface type. For more information, use the question mark (?) online help function.
instance	(Optional) Either a physical interface instance or a virtual interface instance as follows: •Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation. –rack: Chassis number of the rack. –slot: Physical slot number of the modular services card or line card. –module: Module number. A physical layer interface module (PLIM) is always 0. –port: Physical port number of the interface. Note In references to a Management Ethernet interface located on a route processor card, the physical slot number is alphanumeric (RP0 or RP1) and the module is CPU0. Example: interface MgmtEth0/RP1/CPU0/0. •Virtual interface instance. Number range varies depending on interface type. For more information about the syntax for the router, use the question mark (?) online help function.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was 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.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Debugging output is assigned high priority in the CPU process and, therefore, can affect system performance. For more information about the impact on system performance when using debug commands, refer to Using Debug Commands on Cisco IOS XR Software.

When an interface is specified in the command syntax, debugging is turned on for the specified interface. Not specifying the interface turns on debugging for all interfaces.

Task ID

Task ID	Operations
cdp	read

Examples

The following example shows how to enable debugging output for packet information processed by CDP:

RP/0/RP0/CPU0:router# debug cdp xxx