Table Of Contents
IS-IS Debug Commands on Cisco IOS XR Software
debug isis adjacencies
debug isis configuration
debug isis dis-elections
debug isis local-updates
debug isis mpls traffic-eng
debug isis packet-errors
debug isis route
debug isis spf
debug isis startup
debug isis update
IS-IS Debug Commands on Cisco IOS XR Software
This chapter describes the commands used to debug the Intermediate System-to-Intermediate System (IS-IS) protocol on Cisco IOS XR software.
debug isis adjacencies
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) maintenance of adjacencies including the sending and receiving of hello packets, use the debug isis adjacencies command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] adjacencies [interface type instance] [internal] [level {1 | 2}]
[lsp lsp-id] [restarts] [summary | detail] [topology {ipv4 | ipv6} unicast] [only]
no debug isis [instance instance-id] adjacencies [interface type instance] [internal] [level {1 | 2}]
[lsp lsp-id] [restarts] [summary| detail] [topology {ipv4 | ipv6} unicast] [only]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
interface
|
(Optional) Displays debugging output for an interface.
|
type
|
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.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
lsp lsp-id
|
(Optional) Displays debugging output for a specific link-state packet (LSP).
|
restarts
|
(Optional) Displays debugging output for the processing of neighbor restart requests.
|
summary
|
(Optional) Displays debugging output for adjacency change states.
|
topology {ipv4 | ipv6} unicast
|
(Optional) Displays debugging output for a specific topology. The debug output can be filtered by IPv4 or IPv6 unicast topology.
|
detail
|
(Optional) Enables detailed debug output including incoming hello handling and outgoing hello generation.
There are multiple filters available under the detail option. They are:
• interface—Filter IS-IS debug by interface.
• level—Filter IS-IS debug by level. Range is 1 to 2.
• lsp-id—Filter IS-IS debug by LSP ID.
• topology—Filter IS-IS debug by topology.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis adjacencies 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.
Use the debug isis adjacencies command to display the handling of hello packets, the sending of hello packets, and timer events relating to adjacencies. The command is also used to display neighbor restart requests.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis adjacencies command:
RP/0/RP0/CPU0:router# debug isis instance isp adjacencies
RP/0/RP0/CPU0:Jun 21 00:48:03.656 : isis[517]: SEND L1 LAN IIH on GigabitEthernet0/1/0/2:
LAN ID router-2.01, 1 neighbors, Holdtime 30s, Length 1497 RP/0/RP0/CPU0:Jun 21
00:48:05.241 : isis[517]: RECV L1 LAN IIH from GigabitEthernet0/1/0/2 SNPA 0012.da6b.68aa:
System ID router-2, Holdtime 10, LAN ID router-2.01, length 1497
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis configuration
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) configuration including interface events, use the debug isis configuration command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] configuration [interface type instance] [internal] [level {1 | 2}]
[summary | detail] [topology {ipv4 | ipv6} unicast] [only]
no debug isis [instance instance-id] configuration [interface type instance] [internal] [level {1 |
2}] [summary | detail] [topology {ipv4 | ipv6} unicast] [only]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
interface
|
(Optional) Displays debugging output for an interface.
|
type
|
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.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
summary
|
(Optional) Displays debugging output for important configuration events. For example, the creation of areas and topologies.
|
topology {ipv4 | ipv6} unicast
|
(Optional) Displays debugging output for a specific topology. The debug output can be filtered by IPv4 or IPv6 unicast topology.
|
detail
|
(Optional) Enables detailed debug output for each configuration event.
There are multiple filters available under the detail option. They are:
• interface—Filter IS-IS debug by interface.
• level—Filter IS-IS debug by level. Range is 1 to 2.
• lsp-id—Filter IS-IS debug by LSP ID.
• topology—Filter IS-IS debug by topology.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis configuration 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.
Use the debug isis configuration command when investigating problems during the initialization of the IS-IS process, the verification and handling of configuration changes, and interface state changes such as interaction with the Interface Manager (IM) and IP-asynchronous response mode (ARM).
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis configuration command:
RP/0/RP0/CPU0:router# debug isis instance isp configuration
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# router isis isp
RP/0/RP0/CPU0:router(config-isis)# interface loopback 0
RP/0/RP0/CPU0:router(config-isis-if)# address-family ipv4 unicast
RP/0/RP0/CPU0:router(config-isis-if-af)# commit
RP/0/RP0/CPU0:Jun 21 01:18:01.848 : isis[517]: Intf Loopback0: Interface configured
RP/0/RP0/CPU0:Jun 21 01:18:01.853 : isis[517]: Intf Loopback0: IPv4 Unicast: Prefix
advertisement configured RP/0/RP0/CPU0:Jun 21 01:18:01.854 : isis[517]: Intf Loopback0:
IPv4 Unicast: Adjacency formation configured RP/0/5/CPU0:Jun 21 01:18:01.910 : isis[517]:
Intf Loopback0: IPv4 Unicast: New advertised prefix: 192.168.10.10/32 RP/0/RP0/CPU0:Jun 21
01:18:01.912 : isis[517]: Level-1: IPv4 Router ID Change: GigabitEthernet0/1/0/2 ->
Loopback0 RP/0/RP0/CPU0:Jun 21 01:18:01.914 : isis[517]: Intf Loopback0: Standard (IPv4
Unicast): Link Topology ready to form adjacencies RP/0/RP0/CPU0:Jun 21 01:18:01.915 :
isis[517]: Intf Loopback0: Interface starting to send hellos
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis dis-elections
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) designated elections on LAN interfaces, use the debug isis dis-elections command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] dis-elections [interface type instance] [internal] [level {1 | 2}]
[summary | detail] [only]
no debug isis [instance instance-id] dis-elections [interface type instance] [internal] [level {1 |
2}] [summary | detail] [only]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
interface
|
(Optional) Displays debugging output for an interface.
|
type
|
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.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
summary
|
(Optional) Displays debugging output for changes to elected DIS.
|
detail
|
(Optional) Enables detailed debug output for each candidate in a DIS election
There are multiple filters available under the detail option. They are:
• interface—Filter IS-IS debug by interface.
• level—Filter IS-IS debug by level. Range is 1 to 2.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis dis-elections 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.
Use the debug isis dis-elections command to display information on scheduling and running DIS elections.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis dis-elections command:
RP/0/RP0/CPU0:router# debug isis instance isp dis-elections
RP/0/RP0/CPU0:Jun 21 01:22:38.122 : isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS:
router-1 triggers DIS election (local priority change) ...
RP/0/RP0/CPU0:Jun 21 01:22:38.134 : isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS: Run DIS
election ...
RP/0/RP0/CPU0:Jun 21 01:22:38.135 : isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS:
Uninstall the old DIS, router-2 (circuit number 1) RP/0/RP0/CPU0:Jun 21 01:22:38.136 :
isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS: Purge DIS Pseudonode LSP
0000.0000.0022.01-00 RP/0/RP0/CPU0:Jun 21 01:22:38.137 : isis[517]: Intf
GigabitEthernet0/1/0/2 L1 DIS: Install ourselves (circuit number 1) as the new DIS
RP/0/RP0/CPU0:Jun 21 01:22:38.209 : isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS:
router-2 triggers DIS election (neighbor LAN ID change) ...
RP/0/RP0/CPU0:Jun 21 01:22:38.228 : isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS: Run DIS
election ...
RP/0/RP0/CPU0:Jun 21 01:22:38.229 : isis[517]: Intf GigabitEthernet0/1/0/2 L1 DIS: No
change (it's us, circuit number 1)
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis local-updates
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) generation of local system and pseudo-node link-state packets (LSPs), use the debug isis local-updates command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] local-updates [internal] [level {1 | 2}] [node-number number]
[summary | detail] [topology {ipv4 | ipv6} unicast] [verbose] [only]
no debug isis [instance instance-id] local-updates [internal] [level {1 | 2}] [node-number
number] [summary | detail] [topology {ipv4 | ipv6} unicast] [verbose] [only]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
node-number number
|
(Optional) Displays debugging output for a node. Range is 0 to 255.
|
summary
|
(Optional) Displays an overview of LSP generation events.
|
topology {ipv4 | ipv6} unicast
|
(Optional) Displays debugging output for a specific topology. The debug output can be filtered by IPv4 or IPv6 unicast topology.
|
verbose
|
(Optional) Displays debugging output for detail Sub-type, length, values (TLVs).
|
detail
|
(Optional) Displays debugging output for each link and prefix.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis local-updates 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.
Use the debug isis local-updates command to display local system and pseudo-node link-state packet (LSP) activities.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis local-updates command:
RP/0/RP0/CPU0:router# debug isis instance isp local-updates
RP/0/RP0/CPU0:Jun 21 01:33:23.264 : isis[517]: L1 System Adv: LSP generation required
because of 'configuration change' on GigabitEthernet0/1/0/2: generation scheduled with
enforced delay of 2000ms RP/0/RP0/CPU0:Jun 21 01:33:23.265 : isis[517]: L1 System Adv: LSP
generation required because of 'connected IP down' on Loopback0: generation rescheduled
with initial delay of 50ms RP/0/RP0/CPU0:Jun 21 01:33:23.345 : isis[517]: L1 System Adv:
Building LSP ...
RP/0/RP0/CPU0:Jun 21 01:33:23.345 : isis[517]: L1 System Adv: Building fragment 0 seq 0xd
RP/0/RP0/CPU0:Jun 21 01:33:23.347 : isis[517]: L1 System Adv: Standard (IPv4 Unicast): Add
links (OVL: no; ATT: no; TE: no) RP/0/RP0/CPU0:Jun 21 01:33:23.350 : isis[517]: L1 System
Adv: IPv4 Unicast: Add Narrow prefixes RP/0/RP0/CPU0:Jun 21 01:33:23.351 : isis[517]: L1
System Adv: LSP build complete (1 fragments)
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis mpls traffic-eng
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) Multiprotocol Label Switching (MPLS) traffic engineering operation, use the debug isis mpls traffic-eng command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] mpls traffic-end [advertisements | links | tunnels] [interface
type instance] [internal] [level {1 | 2}] [lsp lsp-id] [only] [detail]
no debug isis [instance instance-id] mpls traffic-end [advertisements | links | tunnels] [interface
type instance] [internal] [level {1 | 2}] [lsp lsp-id] [only] [detail]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
advertisements
|
(Optional) Displays debugging output for advertisement flooded in LSPs.
|
links
|
(Optional) Displays debugging output for local link information.
|
tunnels
|
(Optional) Displays debugging output for autoroute announce tunnels.
|
interface
|
(Optional) Displays debugging output for an interface.
|
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.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
lsp lsp-id
|
(Optional) Displays debugging output for a specific LSP.
|
detail
|
(Optional) Displays detailed debugging output.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis mpls traffic-eng 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.
Use the debug isis mpls traffic-eng command to display MPLS traffic engineering activities.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis mpls traffic-eng command:
RP/0/RP0/CPU0:router# debug isis instance isp mpls traffic-eng
RP/0/RP0/CPU0:Jun 21 11:12:49.265 : isis[369]: Cfg: IPv4 Unicast: MPLS TE Level: ADD
'Level-2'
RP/0/RP0/CPU0:Jun 21 11:12:49.268 : isis[369]: Cfg: IPv4 Unicast: MPLS TE Router ID: ADD
'Loopback110'
RP/0/RP0/CPU0:Jun 21 11:12:49.656 : isis[369]: TE Link: L2 POS0/1/0/0: SEND: Adjacency
change: 2000.0000.0026.00 (11.3.1.2) up RP/0/RP0/CPU0:Jun 21 11:12:50.631 : isis[369]: TE
Adv: L2 gr28-5-6.00: SEND: Router node; 4 links; fragment ID 0; flag 0x0)
RP/0/RP0/CPU0:Jun 21 11:12:59.362 : isis[369]: TE Adv: L2 sr1.00 (11.8.1.3): BUILD SUBTLV:
Skip (no link information found) RP/0/RP0/CPU0:Jun 21 11:12:59.362 : isis[369]: TE Adv: L2
router-2.00 (11.3.1.3): BUILD SUBTLV: Add (64 bytes)
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis packet-errors
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) format, checksum, and authentication errors in received packets, use the debug isis packet-errors command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] packet-errors [interface type instance] [detail [only]]
no debug isis [instance instance-id] packet-errors [interface type instance] [detail[only]]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
interface
|
(Optional) Displays debugging output for an interface.
|
type
|
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.
|
detail
|
(Optional) Displays debug output for dump packets with format or checksum errors.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis packet-errors 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.
Use the debug isis packet-errors command to diagnose problems where packets are dropped due to a format, checksum, or authentication error.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis packet-errors command:
RP/0/RP0/CPU0:router# debug isis instance isp packet-errors
RP/0/RP0/CPU0:Jun 21 01:54:19.652 : isis[517]: %ROUTING-ISIS-5-AUTH_FAILURE_DROP : Dropped
L2 LAN IIH from GigabitEthernet0/1/0/2 SNPA 0013.5f12.64ab due to authentication TLV not
found RP/0/RP0/CPU0:Jun 21 01:54:19.652 : isis[517]: BAD L2 LAN IIH rcvd from
GigabitEthernet0/1/0/2 SNPA 0013.5f12.64ab: dropped because authentication TLV not found
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis route
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) local routing table, use the debug isis route command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] route [ip-address [longer-prefixes]] [internal] [prefix-list
prefix-list-name] [topology {ipv4 | ipv6} unicast] [verbose] [only] [detail]
no debug isis [instance instance-id] route [ip-address [longer-prefixes]] [internal] [prefix-list
prefix-list-name] [topology {ipv4 | ipv6} unicast] [verbose] [only] [detail]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
ip-address
|
(Optional) An IPv4 or IPv6 address prefix to limit the debug output.
|
longer-prefixes
|
(Optional) Displays the debugging output for longer prefixes of the ip-address filter.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
prefix-list prefix-list-name
|
(Optional) Displays debugging output limited to an access list.
|
topology {ipv4 | ipv6} unicast
|
(Optional) Displays debugging output for a specific topology. The debug output can be filtered by IPv4 or IPv6 unicast topology.
|
verbose
|
(Optional) Displays detailed debugging output.
|
detail
|
(Optional) Displays detailed debugging output including events that result in no change to the routing table.
|
only
|
(Optional) Enables debug output only for the filter value.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis route 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.
Use the debug isis route command to debug maintenance of the IS-IS local routing table.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis route command:
RP/0/RP0/CPU0:router# debug isis instance isp route
RP/0/RP0/CPU0:Jun 21 11:45:57.719 : isis[236]: Cfg: IPv6 Unicast: Redistribute isis isp-2:
ADD 'level-1 @ Internal metric 0 using route policy (none)'
RP/0/RP0/CPU0:Jun 21 11:45:57.809 : isis[236]: IPv6 Unicast Redistributed Route
3002::500/120: Add @ L1: 0 (isis isp-2), L2 unreachable (none) RP/0/RP0/CPU0:Jun 21
11:45:57.810 : isis[236]: IPv6 Unicast Redistributed Route 3ffe::/64: Add @ L1: 0 (isis
isp-2), L2 unreachable (none) RP/0/RP0/CPU0:Jun 21 11:45:57.870 : isis[236]: IPv6 Unicast
Connected Route 3ffe:390b::/64: Add (add Loopback0) RP/0/RP0/CPU0:Jun 21 11:45:57.872 :
isis[236]: IPv6 Unicast Connected Route 4ffe::4:0/112: Add (add POS0/1/0/1)
RP/0/RP0/CPU0:Jun 21 11:46:17.773 : isis[236]: IPv6 Unicast Own Route 2002::/112: Install
new @ L1 metric 20 (router-2)
RP/0/RP0/CPU0:Jun 21 11:46:17.774 : isis[236]: IPv6 Unicast Own Route 2002::/112:
Install next hop via fe80::3139:30ff:fe31:5534 (POS0/1/0/1) (router-2)
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis spf
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) scheduling and running of route calculations including incremental shortest path first (SPF) algorithms and partial route calculations (PRCs), use the debug isis spf command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] spf [full | incremental | prc | trigger] [ip-address] [internal]
[level {1 | 2}] [links] [lsp lsp-id] [prefix-list prefix-list-name] [summary | detail] [topology
{ipv4 | ipv6} unicast] [verbose] [only]
no debug isis [instance instance-id] spf [full | incremental | prc | trigger] [ip-address] [internal]
[level {1 | 2}] [links] [lsp lsp-id] [prefix-list prefix-list-name] [summary | detail] [topology
{ipv4 | ipv6} unicast] [verbose] [only]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
full
|
(Optional) Displays debugging output for full SPF calculations.
|
incremental
|
(Optional) Displays debugging output for incremental SPF calculations.
|
prc
|
(Optional) Displays debugging output for partial route calculations.
|
trigger
|
(Optional) Displays debugging output for trigger decisions.
|
ip-address
|
(Optional) An IPv4 or IPv6 address prefix to limit the debug output.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
lsp lsp-id
|
(Optional) Displays debugging output for a specific LSP.
|
prefix-list prefix-list-name
|
(Optional) Displays debugging output limited to an access list.
|
summary
|
(Optional) Displays an overview of debugging output for route calculation events.
|
topology {ipv4 | ipv6} unicast
|
(Optional) Displays debugging output for a specific topology. The debug output can be filtered by IPv4 or IPv6 unicast topology.
|
verbose
|
(Optional) Displays detailed debugging output for each prefix.
|
only
|
(Optional) Enables debug output only for the filter value.
|
detail
|
(Optional) Displays debugging output for the operation of the algorithm on each node.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis spf 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.
Use the debug isis spf command to display the scheduling and operation of routing calculations.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis spf command:
RP/0/RP0/CPU0:router# debug isis instance isp spf
RP/0/RP0/CPU0:Jun 21 11:51:54.930 : isis[236]: Standard (IPv4 Unicast) L1 Trigger: Full
SPF required due to 'new LSP 0' in r3.00-00: Full SPF will be executed manually later in
the restart RP/0/RP0/CPU0:Jun 21 11:51:54.931 : isis[236]: Standard (IPv4 Unicast) L1
Trigger: Full SPF required due to 'new LSP 0' in r3.01-00: Full SPF will be executed
manually later in the restart RP/0/RP0/CPU0:Jun 21 11:52:14.667 : isis[236]: Standard
(IPv4 Unicast) L1 FSPF: Route calculation starting RP/0/RP0/CPU0:Jun 21 11:52:14.705 :
isis[236]: Standard (IPv4 Unicast) L1 FSPF: r3.00: Move to PATHS, path metric 30, 1 next
hops:
RP/0/RP0/CPU0:Jun 21 11:52:14.706 : isis[236]: Standard (IPv4 Unicast) L1 FSPF: r3.00:
router-2 (POS0/1/0/1)
RP/0/RP0/CPU0:Jun 21 11:52:14.719 : isis[236]: Standard (IPv4 Unicast) L1 FSPF: r3.01:
Move to PATHS, path metric 40, 1 next hops:
RP/0/RP0/CPU0:Jun 21 11:52:14.719 : isis[236]: Standard (IPv4 Unicast) L1 FSPF: r3.01:
router-2 (POS0/1/0/1)
RP/0/RP0/CPU0:Jun 21 11:52:15.610 : isis[236]: Standard (IPv4 Unicast) L1 FSPF: Update
default route after SPF (purge) RP/0/RP0/CPU0:Jun 21 11:52:15.611 : isis[236]: Standard
(IPv4 Unicast) L1 FSPF: Route calculation complete: duration 944ms/454ms (real/CPU); 531
nodes on SPT
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis startup
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) process initialization for nonstop forwarding (NSF) restarts and cold starts, use the debug isis startup command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] startup [interface type instance] [internal] [level {1 | 2}] [lsp
lsp-id] [verbose] [only] [detail]
no debug isis [instance instance-id] startup [interface type instance] [internal] [level {1 | 2}] [lsp
lsp-id] [verbose] [only] [detail]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
interface
|
(Optional) Displays debugging output for an interface.
|
type
|
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.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
lsp lsp-id
|
(Optional) Displays debugging output for a specific LSP.
|
verbose
|
(Optional) Displays detailed debugging output.
|
only
|
(Optional) Enables debug output only for the filter value.
|
detail
|
(Optional) Displays debugging output for key events for individual interfaces, adjacencies, and LSPs.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis startup 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.
Use the debug isis startup command to track the progress of a process restart using Cisco NSF, IETF NSF, or a cold restart.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis startup command:
RP/0/RP0/CPU0:router# debug isis instance isp startup
RP/0/RP0/CPU0:Jun 21 11:36:16.290 : isis[236]: Process Initialization: IS-IS instance
'isp' is initializing (binary isis) ...
RP/0/RP0/CPU0:Jun 21 11:36:16.643 : isis[236]: Cisco NSF: Controlled restart starts with
time budget of 60 s.
RP/0/RP0/CPU0:Jun 21 11:36:16.643 : isis[236]: %ROUTING-ISIS-6-INFO_STARTUP_START : Cisco
NSF controlled start beginning RP/0/RP0/CPU0:Jun 21 11:36:17.077 : isis[236]: Cisco NSF -
SSM-INIT: 1 interfaces restored from checkpoint RP/0/RP0/CPU0:Jun 21 11:36:17.395 :
isis[236]: Cfg: NSF Restart Flavor: CHANGE 'Cold' -> 'Cisco NSF'
RP/0/RP0/CPU0:Jun 21 11:36:17.680 : isis[236]: Process Initialization: IS-IS instance
'isp' initialization complete RP/0/RP0/CPU0:Jun 21 11:36:17.707 : isis[236]: Cisco NSF -
SSM-INIT: Initialize Restart Resources RP/0/RP0/CPU0:Jun 21 11:36:17.707 : isis[236]:
Cisco NSF - SSM-INIT: Phase Result - Proceed RP/0/RP0/CPU0:Jun 21 11:36:17.708 :
isis[236]: Cisco NSF - NSF-CISCO-INIT: Initialize Cisco-NSF resources RP/0/RP0/CPU0:Jun 21
11:36:17.709 : isis[236]: Cisco NSF - NSF-CISCO-INIT: Phase Result - Proceed
RP/0/RP0/CPU0:Jun 21 11:36:17.709 : isis[236]: Cisco NSF - NSF-CISCO-IDB-WAIT: Wait for
interfaces to be ready to run RP/0/RP0/CPU0:Jun 21 11:36:17.711 : isis[236]: Cisco NSF -
NSF-CISCO-IDB-WAIT: Waiting for 1 of 1 configured interfaces to be ready (first check)
RP/0/RP0/CPU0:Jun 21 11:36:17.711 : isis[236]: Cisco NSF - NSF-CISCO-IDB-WAIT: Phase
Result - Retry/Abort (No interfaces ready) RP/0/RP0/CPU0:Jun 21 11:36:17.726 : isis[236]:
Memory state change: Normal - ignore (uninteresting state) RP/0/RP0/CPU0:Jun 21
11:36:17.802 : isis[236]: Cisco NSF - NSF-CISCO-IDB-WAIT: Wait for interfaces to be ready
to run (retry) RP/0/RP0/CPU0:Jun 21 11:36:17.802 : isis[236]: Cisco NSF -
NSF-CISCO-IDB-WAIT: Waiting for 0 of 1 configured interfaces to be ready (change since
last check) RP/0/RP0/CPU0:Jun 21 11:36:17.803 : isis[236]: Cisco NSF - NSF-CISCO-IDB-WAIT:
Phase Result - Proceed RP/0/RP0/CPU0:Jun 21 11:36:17.805 : isis[236]: Cisco NSF -
NSF-CISCO-ADJ-READ: Restore Adjacency DB from checkpoint table RP/0/RP0/CPU0:Jun 21
11:36:17.817 : isis[236]: Cisco NSF - NSF-CISCO-ADJ-READ: Phase Result - Proceed (1 L1 and
0 L2 adjacencies restored) RP/0/RP0/CPU0:Jun 21 11:36:17.815 : isis[236]:
%ROUTING-ISIS-4-ADJCHANGE : Adjacency to 2000.0000.0025 (POS0/1/0/1) (L1) Up, Checkpoint
restore RP/0/RP0/CPU0:Jun 21 11:36:17.818 : isis[236]: Cisco NSF - NSF-CISCO-DIS-ELECT:
Run DIS elections.
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|
debug isis update
To display debugging information for the Intermediate System-to-Intermediate System (IS-IS) synchronization of the link-state packet (LSP) database with neighbors, use the debug isis update command in EXEC mode. To turn off debugging output, use the no form of this command.
debug isis [instance instance-id] update [lsp | snp] [interface type instance] [internal] [level {1 |
2}] [lsp lsp-id] [summary | detail] [timers] [only]
no debug isis [instance instance-id] update [lsp | snp] [interface type instance] [internal] [level
{1 | 2}] [lsp lsp-id] [summary | detail] [timers] [only]
Syntax Description
instance instance-id
|
(Optional) Displays debugging output for the specified IS-IS instance only. The instance-id argument is the instance identifier (alphanumeric) defined by the router isis command.
|
lsp
|
(Optional) Displays debugging output for sending and receiving LSPs.
|
snp
|
(Optional) Displays debugging output for sending and receiving SNPs.
|
interface
|
(Optional) Displays debugging output for an interface.
|
type
|
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.
|
internal
|
(Optional) Displays debugging output for internal or development use.
|
level {1 | 2}
|
(Optional) Displays debugging output for Level 1 or Level 2.
|
lsp lsp-id
|
(Optional) Displays debugging output for a specific link-state packet (LSP).
|
summary
|
(Optional) Displays debugging output for changes to the LSP database.
|
timers
|
(Optional) Displays debugging output for timer expiry events.
|
only
|
(Optional) Enables debug output only for the filter value.
|
detail
|
(Optional) Displays debugging output for processing of each LSP or SNP sent or received.
|
Defaults
instance-id: If none specified, debug for all IS-IS instances is displayed.
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.
|
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 isis update 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.
Use the debug isis update command to display the operation of the update process including LSP packet processing, SNP packet processing, and the handling of update timers.
Task ID
Task ID
|
Operations
|
isis
|
read, write
|
Examples
The following is sample output from the debug isis update command:
RP/0/RP0/CPU0:router# debug isis instance isp update
RP/0/RP0/CPU0:Jun 21 11:33:47.078 : isis[236]: LSP DB: L1 LSP r8.00-00 sn 0x16b cs 0x22b3
ht 1199 REP L1 LSP r8.00-00 sn 0x16a cs 0x24b2 ht 299 RP/0/RP0/CPU0:Jun 21 11:33:47.262 :
isis[236]: SEND L1 PSNP on POS0/1/0/1: length 99 RP/0/RP0/CPU0:Jun 21 11:33:47.693 :
isis[236]: RECV L1 LSP r35.00-00 from POS0/1/0/1: Seq 0x16b; Checksum 0x9db9; Holdtime
1199; Length 453
Related Commands
Command
|
Description
|
undebug
|
Enters debug mode to disable or reset multiple active debug command sessions.
|