Table Of Contents

Cisco Express Forwarding Debug Commands on Cisco IOS XR Software

debug cef api

debug cef drops

debug cef errors

debug cef events

debug cef extclient

debug cef lib

debug cef packet

debug cef platform

debug cef platform adj

debug cef platform common

debug cef platform ea

debug cef prefix-ltraces

debug cef table

Cisco Express Forwarding Debug Commands on Cisco IOS XR Software

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This chapter describes the commands used to debug the Cisco Express Forwarding software on Cisco IOS XR software.

debug cef api

To enable Cisco Express Forwarding (CEF) application program interface (API) debugging, use the debug cef command in EXEC mode. To disable CEF API debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] api {events | errors} [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] api {events | errors} [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
events	Specifies CEF API event debug information.
errors	Specifies CEF API error debug information.
access-list	(Optional) Name of a specific access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF API event debugging:

RP/0/RP0/CPU0:router# debug cef api events 

debug cef drops

To enable Cisco Express Forwarding (CEF) dropped packet debugging, use the debug cef drops command in EXEC mode. To disable CEF dropped packet debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] drops [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] drops [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a specific access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

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	The rpf keyword was removed. The following keywords and arguments were added: •mpls •level level •vrf vrf-name
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF dropped packets debugging:

RP/0/RP0/CPU0:router# debug cef drops

debug cef errors

To enable Cisco Express Forwarding (CEF) error debugging, use the debug cef errors command in EXEC mode. To disable CEF error debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] errors [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] errors [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a specific access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

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	The following keywords and arguments were added: •mpls •access-list •level level •vrf vrf-name
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF error debugging:

RP/0/RP0/CPU0:router# debug cef errors

debug cef events

To enable Cisco Express Forwarding (CEF) event debugging, use the debug cef events command in EXEC mode. To disable CEF event debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] events [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] events [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a particular access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

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	The following keywords and arguments were added: •mpls •level level •vrf vrf-name
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF event debugging:

RP/0/RP0/CPU0:router# debug cef events location 0/2/cp0

debug cef extclient

To enable Cisco Express Forwarding (CEF) external client debugging, use the debug cef extclient command in EXEC mode. To disable CEF external client debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] extclient [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] extclient [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a particular access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF external client debugging:

RP/0/RP0/CPU0:router# debug cef extclient 

debug cef lib

To enable Cisco Express Forwarding (CEF) library debugging, use the debug cef library command in EXEC mode. To disable CEF library debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] lib [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] lib [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a particular access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF library debugging:

RP/0/RP0/CPU0:router# debug cef lib 

debug cef packet

To enable Cisco Express Forwarding (CEF) packet handling debugging, use the debug cef packet command in EXEC mode. To disable CEF packet handling debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] packet [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] packet [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a particular access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

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	The following keywords and arguments were added: •mpls •level level •vrf vrf-name
Release 3.5.0	Glean address resolution debugging example was added for ACL-based forwarding.

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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to debug a glean address resolution for ACL-based forwarding:

RP/0/RP0/CPU0:router# debug cef ipv4 packet level 2 location 0/1/cp0 

RP/0/RP0/CPU0:router# LC/0/1/CPU0:Oct  3 22:48:25.935 : netio[180]: [Th:8, Pr:ipv4] 
IP-CEF(ABF nexthop forwarding) : source 50.60.1.2, replace dest: 50.70.1.2 with 
abf_nexthop: 50.70.1.2

LC/0/1/CPU0:Oct  3 22:48:25.938 : netio[180]: [Th:8, Pr:ipv4] CEF-PKT: Lookup for packet: 
source:50.60.1.2 dest:50.70.1.2 tbl 0xe0000000 dir 1 ext len 20

debug cef platform

To enable Cisco Express Forwarding (CEF) platform debugging, use the debug cef platform command in EXEC mode. To disable CEF platform debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] platform {ipv4 | ipv6 | mpls} {all | error | events | info | trace | verbose} [location node-id]

no debug cef [ipv4 | ipv6 | mpls] platform {ipv4 | ipv6 | mpls} {all | error | events | info | trace | verbose} [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
ipv4	Displays IPv4 platform debugging information.
ipv6	Displays IPv6 platform debugging information.
mpls	Displays Multiprotocol Label Switching (MPLS) platform debugging information.
all	Displays all platform debugging information.
error	Displays platform error debugging information.
events	Displays platform events debugging information.
info	Displays platform information debugging information.
trace	Displays platform trace debugging information.
verbose	Displays platform verbose debugging information.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF platform IPv4 error debugging:

RP/0/RP0/CPU0:router# debug cef platform ipv4 errors 

debug cef platform adj

To enable Cisco Express Forwarding (CEF) platform adjacency debugging, use the debug cef platform adj command in EXEC mode. To disable CEF platform adjacency debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] platform adj {all | error | info} [location node-id]

no debug cef [ipv4 | ipv6 | mpls] platform adj {all | error | info} [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
all	Displays all adjacency debugging information.
error	Displays adjacency error debugging information.
info	Displays adjacency debugging information.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF platform adjacency debugging:

RP/0/RP0/CPU0:router# debug cef platform adj all 

debug cef platform common

To enable Cisco Express Forwarding (CEF) platform common debugging, use the debug cef platform common command in EXEC mode. To disable CEF platform common debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] platform common {all | error | events | info | trace | verbose} [location node-id]

no debug cef [ipv4 | ipv6 | mpls] platform common {all | error | events | info | trace | verbose} [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
all	Displays all platform common debugging information.
error	Displays platform common errors debugging information.
events	Displays platform common events debugging information.
info	Displays platform common debugging information.
trace	Displays platform common trace debugging information.
verbose	Displays platform common verbose debugging information.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and the Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF platform common debugging:

RP/0/RP0/CPU0:router# debug cef platform common all 

debug cef platform ea

To enable Cisco Express Forwarding (CEF) platform execution agent (EA) debugging, use the debug cef platform ea command in EXEC mode. To disable CEF platform EA debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] platform ea {ipv4 | ipv6 | mpls} {error | events | info | trace | verbose} [location node-id]

no debug cef [ipv4 | ipv6 | mpls] platform ea {ipv4 | ipv6 | mpls} {error | events | info | trace | verbose} [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
ipv4	Displays IPv4 EA debugging information.
ipv6	Displays IPv6 EA debugging information.
mpls	Displays Multiprotocol Label Switching (MPLS) EA debugging information.
error	Displays platform common errors debugging information.
events	Displays platform common events debugging information.
info	Displays platform common debugging information.
trace	Displays platform common trace debugging information.
verbose	Displays platform common verbose debugging information.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF platform EA IPv4 error debugging:

RP/0/RP0/CPU0:router# debug cef platform EA ipv4 errors

debug cef prefix-ltraces

To enable Cisco Express Forwarding (CEF) logging of prefix ltraces, use the debug cef prefix-ltraces command in EXEC mode. To disable CEF logging of prefix ltraces, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] prefix-ltraces [location node-id]

no debug cef [ipv4 | ipv6 | mpls] prefix-ltraces [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 3.4.0	This command was introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	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.

---

Caution The debug cef prefixes-ltraces command generates a substantial amount of output. Use the command only when traffic on the IP network is low so that other activity on the system is not adversely affected.

---

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF prefix ltrace logging:

RP/0/RP0/CPU0:router# debug cef prefixes-ltraces 

debug cef table

To enable Cisco Express Forwarding (CEF) table debugging, use the debug cef table command in EXEC mode. To disable CEF table debugging, use the no form of this command.

debug cef [ipv4 | ipv6 | mpls] table [access-list] [level level] [vrf vrf-name] [location node-id]

no debug cef [ipv4 | ipv6 | mpls] table [access-list] [level level] [vrf vrf-name] [location node-id]

Syntax Description

ipv4	(Optional) Specifies IP Version 4 (IPv4) address prefixes.
ipv6	(Optional) Specifies IP Version 6 (IPv6) address prefixes.
mpls	(Optional) Specifies Multiprotocol Label Switching (MPLS)-specific debugging information.
access-list	(Optional) Name of a particular access list. The name cannot contain a space or quotation mark; it may contain numbers.
level level	(Optional) Specifies the maximum verbosity level. Range is 0 to 2.
vrf vrf-name	(Optional) Specifies a VPN routing and forwarding (VRF) instance. The vrf-name argument can be specified as an arbitrary string. The strings "default" and "all" are reserved VRF names.
location node-id	(Optional) Specifies a location. The node-id argument is entered in the rack/slot/module notation.

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	The following keywords and arguments were added: •mpls •level level •vrf vrf-name
Release 3.5.0	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.

Task ID

Task ID	Operations
cef	read, write

Examples

The following example shows how to enable CEF tables debugging:

RP/0/RP0/CPU0:router# debug cef table location 0/2/cp0