Guest

Cisco IOS Software Releases 12.2 S

MPLS High Availability: Command Changes

  • Viewing Options

  • PDF (348.7 KB)
  • Feedback
MPLS High Availability: Command Changes

Table Of Contents

MPLS High Availability: Command Changes

Contents

Information About MPLS High Availability: Command Changes

MPLS Replacement Commands for Tag-Switching Commands

New Command Defaults

MPLS MTU Command Changes

Deleted Commands

Replaced Commands

How to Configure MPLS High Availability: Command Changes

Configuration Examples for MPLS High Availability: Command Changes

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference

debug mpls packets

mpls mtu

show atm vc

show mpls forwarding-table

show tech-support mpls

Feature Information for MPLS High Availability: Command Changes


MPLS High Availability: Command Changes


First Published: August 11, 2004
Last Updated: August 21, 2007

This feature module details changes to commands that are required to support updates to the Multiprotocol Label Switching (MPLS) High Availability (HA) feature.

In Cisco IOS Releases 12.2(25)S, 12.2(28)SB, 12.2(33)SRA, and 12.2(33)SXH, the MPLS control plane software is enhanced to work in MPLS HA environments. The changes made the control plane software more modular, which helps MPLS support MPLS HA applications. Some of the control plane software changes also made MPLS more scalable and flexible.

Changes to the MPLS Forwarding Infrastructure (MFI) and the Cisco Express Forwarding component introduced new commands and changed other existing commands. MFI replaced the Label Forwarding Information Base (LFIB) and is responsible for managing MPLS data structures used for forwarding.

Finding Feature Information in This Module

Your Cisco IOS software release may not support all of the features documented in this module. To reach links to specific feature documentation in this module and to see a list of the releases in which each feature is supported, use the "Feature Information for MPLS High Availability: Command Changes" section.

Finding Support Information for Platforms and Cisco IOS and Catalyst OS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Contents

Information About MPLS High Availability: Command Changes

How to Configure MPLS High Availability: Command Changes

Configuration Examples for MPLS High Availability: Command Changes

Additional References

Command Reference

Feature Information for MPLS High Availability: Command Changes

Information About MPLS High Availability: Command Changes

Before using MPLS High Availability features, you should understand the following concepts:

MPLS Replacement Commands for Tag-Switching Commands

New Command Defaults

MPLS MTU Command Changes

Deleted Commands

Replaced Commands

MPLS Replacement Commands for Tag-Switching Commands

Starting with Cisco IOS Releases 12.2(25)S, 12.2(28)SB, 12.2(33)SRA and 12.2(33)SXH, all tag-switching commands are obsoleted and are replaced with MPLS command versions. When you enter an obsolte tag-switching command, such as tag-switching ip, you receive the following message:

% Command accepted but obsolete, unreleased, or unsupported; see documentation

Use the MPLS version of the command instead, such as mpls ip.

Support for the tag-switching versions of commands will cease in a future release.

Configuration files that use the tag-switching version of the commands continue to operate. However, running configurations will display the new MPLS versions of the commands.

New Command Defaults

Starting with Cisco IOS Releases 12.2(25)S, 12.2(28)SB, 12.2(33)SRA and 12.2(33)SXH, Label Distribution Protocol (LDP) is the default protocol. In other releases and trains, the default label distribution protocol is Tag Distribution Protocol (TDP). See the mpls label protocol (global configuration) command in the NSF/SSO—MPLS LDP and MPLS LDP Graceful Restart feature for more information.

MPLS MTU Command Changes

The mpls mtu command has changed over the course of the several releases, starting in Cisco IOS Release 12.2(25)S. This section documents the changes implemented in Cisco IOS Release 12.2(25)S. For information about the changes implemented in Cisco IOS Releases 12.2(27)SBC and later releases, see the MPLS MTU Command Changes feature.

In Cisco IOS Release 12.2(25)S, if the interface MTU is less than 1524 bytes, you can set the maximum MPLS MTU to 24 bytes more than the interface MTU. For example, if the interface MTU is set to
1510 bytes, then you can set the maximum MPLS MTU to 1534 bytes (1510 + 24).


Note Although you can set the MPLS MTU to a value greater than the MPLS MTU, it is recommended that you keep the MPLS MTU less than or equal to the interface MTU to prevent the hardware from dropping packets. A best practice is to set the interface MTU of the core-facing interface to a value greater than either the IP MTU or interface MTU of the edge-facing interface.


If the interface MTU is greater than or equal to 1524 bytes, then you can set the maximum MPLS MTU as high as the interface MTU. For example, if the interface MTU is set to 1600 bytes, then you can set the MPLS MTU to a maximum of 1600 bytes. If you set the MPLS MTU higher than the interface MTU, traffic is dropped.

For interfaces that do not allow you to configure the interface MTU value and the interface MTU is
1500 bytes, the MPLS MTU range is 64 to 1524 bytes.

If you upgrade to Cisco IOS Release 12.2(25)S from an earlier release and you have an MPLS MTU setting that does not conform to these guidelines, the MPLS MTU setting is not accepted by the system. If this happens, reconfigure the MPLS MTU setting to conform to the guidelines.

Deleted Commands

The following commands are no longer available in Cisco IOS Releases 12.2(25)S, 12.2(28)SB, 12.2(33)SRA, and 12.2(33)SXH:

debug mpls adjacency

debug mpls lfib cef

debug mpls lfib enc

debug mpls lfib lsp

debug mpls lfib state

debug mpls lfib struct

debug mpls lfib fast-reroute

Replaced Commands

Table 1 lists the commands that use the term tag-switching. Starting with Cisco IOS Releases 12.2(25)S, 12.2(28)SB, 12.2(33)SRA, and 12.2(33)SXH, these commands have been updated with MPLS terminology. Although the tag-switching versions of the commands are obsoleted, the tag-switching commands continue to work, but are not documented.

Please use the MPLS versions of the commands. If you issue a tag-switching command, you receive the following error:

% Command accepted but obsolete, unreleased, or unsupported; see documentation

For information about any of the MPLS commands in Table 1 and Table 2, see the
Cisco IOS Release 12.4 MPLS Command Reference.

Table 1 alphabetically lists the MPLS commands used by the Cisco 7500 series routers that replaced the tag-switching commands.

Table 1 Cisco 7500 Series—MPLS Commands That Replaced Tag-Switching Commands 

This MPLS Command Replaces
This Tag-Switching Command

debug mpls atm-cos

debug tag-switching atm-cos

debug mpls atm-ldp api

debug tag-switching atm-tdp api

debug mpls atm-ldp routes

debug tag-switching atm-tdp routes

debug mpls atm-ldp states

debug tag-switching atm-tdp states

debug mpls events

debug tag-switching events

debug mpls ldp advertisements

debug tag-switching tdp advertisements

debug mpls ldp bindings

debug tag-switching tdp bindings

debug mpls ldp messages

debug tag-switching tdp pies

debug mpls ldp peer state-machine

debug tag-switching tdp peer state-machine

debug mpls ldp session io

debug tag-switching tdp session io

debug mpls ldp session state-machine

debug tag-switching tdp session state-machine

debug mpls ldp targeted-neighbors

debug tag-switching tdp directed-neighbors

debug mpls ldp transport connections

debug tag-switching tdp transport connections

debug mpls ldp transport events

debug tag-switching tdp transport events

debug mpls traffic-eng tunnels events

debug tag-switching tsp-tunnels events

debug mpls traffic-eng tunnels labels

debug tag-switching tsp-tunnels tagging

debug mpls traffic-eng tunnels signalling

debug tag-switching tsp-tunnels signalling

debug mpls xtagatm cross-connect

debug tag-switching xtagatm cross-connect

debug mpls xtagatm errors

debug tag-switching xtagatm errors

debug mpls xtagatm events

debug tag-switching xtagatm events

debug mpls xtagatm vc

debug tag-switching xtagatm vc

mpls atm control-vc

tag-switching atm control-vc

mpls atm cos

tag-switching atm cos

mpls atm disable-headend-vc

tag-switching atm disable-headend-vc

mpls atm multi-vc

tag-switching atm multi-vc

mpls atm vpi

tag-switching atm vpi

mpls atm vp-tunnel

tag-switching atm vp-tunnel

mpls cos-map

tag-switching cos-map

mpls ip (global configuration)

tag-switching ip (global configuration)

mpls ip (interface configuration)

tag-switching ip (interface configuration)

mpls ip default-route

tag-switching ip default-route

mpls ip propagate-ttl

tag-switching ip propagate-ttl

mpls label range

tag-switching tag-range downstream

mpls ldp advertise-labels

tag-switching advertise-tags

mpls ldp atm control-mode

tag-switching atm allocation-mode

mpls ldp atm vc-merge

tag-switching atm vc-merge

mpls ldp discovery

tag-switching tdp discovery

mpls ldp holdtime

tag-switching tdp holdtime

mpls ldp maxhops

tag-switching atm maxhops

mpls mtu

tag-switching mtu

mpls prefix-map

tag-switching prefix-map

mpls request-labels for

tag-switching request-tags for

mpls traffic-eng tunnels

tag-switching tsp-tunnels

show mpls atm-ldp bindings

show tag-switching atm-tdp bindings

show mpls atm-ldp bindwait

show tag-switching atm-tdp bindwait

show mpls atm-ldp capability

show tag-switching atm-tdp capability

show mpls atm-ldp summary

show tag-switching atm-tdp summary

show mpls cos-map

show tag-switching cos-map

show mpls forwarding-table

show tag-switching forwarding-table

show tag-switching forwarding vrf

show mpls interfaces

show tag-switching interfaces

show mpls ldp bindings

show tag-switching tdp bindings

show mpls ldp discovery

show tag-switching tdp discovery

show mpls ldp neighbors

show tag-switching tdp neighbors

show mpls ldp parameters

show tag-switching tdp parameters

show mpls prefix-map

show tag-switching prefix-map

show mpls traffic-eng tunnels

show tag-switching tsp-tunnels

tunnel mode mpls traffic-eng

tunnel mode tag-switching


Table 2 alphabetically lists the MPLS commands used by the Cisco 10000 series routers that replaced the tag-switching commands.

Table 2 Cisco 10000 Series—MPLS Commands That Replaced Tag-Switching Commands 

This MPLS Command Replaces
This Tag-Switching Command

debug mpls events

debug tag-switching events

debug mpls ldp advertisements

debug tag-switching tdp advertisements

debug mpls ldp bindings

debug tag-switching tdp bindings

debug mpls ldp messages

debug tag-switching tdp pies

debug mpls ldp peer state-machine

debug tag-switching tdp peer state-machine

debug mpls ldp session io

debug tag-switching tdp session io

debug mpls ldp session state-machine

debug tag-switching tdp session state-machine

debug mpls ldp targeted-neighbors

debug tag-switching tdp directed-neighbors

debug mpls ldp transport connections

debug tag-switching tdp transport connections

debug mpls ldp transport events

debug tag-switching tdp transport events

debug mpls traffic-eng tunnels events

debug tag-switching tsp-tunnels events

debug mpls traffic-eng tunnels labels

debug tag-switching tsp-tunnels tagging

debug mpls traffic-eng tunnels signalling

debug tag-switching tsp-tunnels signalling

mpls ip (global configuration)

tag-switching ip (global configuration)

mpls ip (interface configuration)

tag-switching ip (interface configuration)

mpls ip default-route

tag-switching ip default-route

mpls ip propagate-ttl

tag-switching ip propagate-ttl

mpls label range

tag-switching tag-range downstream

mpls ldp advertise-labels

tag-switching advertise-tags

mpls ldp discovery

tag-switching tdp discovery

mpls ldp holdtime

tag-switching tdp holdtime

mpls ldp maxhops

tag-switching atm maxhops

mpls mtu

tag-switching mtu

mpls prefix-map

tag-switching prefix-map

mpls request-labels for

tag-switching request-tags for

mpls traffic-eng tunnels

tag-switching tsp-tunnels

show mpls forwarding-table

show tag-switching forwarding-table

show tag-switching forwarding vrf

show mpls interfaces

show tag-switching interfaces

show mpls ldp bindings

show tag-switching tdp bindings

show mpls ldp discovery

show tag-switching tdp discovery

show mpls ldp neighbors

show tag-switching tdp neighbors

show mpls ldp parameters

show tag-switching tdp parameters

show mpls prefix-map

show tag-switching prefix-map

show mpls traffic-eng tunnels

show tag-switching tsp-tunnels

tunnel mode mpls traffic-eng

tunnel mode tag-switching


How to Configure MPLS High Availability: Command Changes

There are no cofiguration tasks for this feature.

Configuration Examples for MPLS High Availability: Command Changes

There are no configuration examples for this feature.

Additional References

The following sections provide references related to the MPLS High Availability feature.

Related Documents

Related Topic
Document Title

MPLS HA for VPNS

NSF/SSO-MPLS VPN

MPLS HA for LDP

NSF/SSO-MPLS LDP and MPLS LDP Graceful Restart

MPLS HA and other applications

MPLS High Availability: Overview

Stateful switchover

Stateful Switchover

MPLS Label Distribution Protocol

MPLS Label Distribution Protocol (LDP)

Cisco nonstop forwarding

Cisco Nonstop Forwarding

MPLS MTU command changes implemented in
Cisco IOS Releases 12.2(27)SBC and later releases.

MPLS MTU Command Changes

Cisco IOS Release 12.4 commands

Cisco IOS Release 12.4 MPLS Command Reference


Standards

Standard
Title

None


MIBs

MIB
MIBs Link

None

To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml


RFCs

RFC
Title

None


Technical Assistance

Description
Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password. If you have a valid service contract but do not have a user ID or password, you can register on Cisco.com.

http://www.cisco.com/techsupport


Command Reference

This section documents only commands that are new or modified.

debug mpls packets

mpls mtu

show atm vc

show mpls forwarding-table

show tech-support mpls

debug mpls packets

To display Multiprotocol Label Switching (MPLS) labeled packets switched by the host router, use the debug mpls packets command in privileged EXEC mode. To disable debugging output, use the no form of this command.

debug mpls packets [interface]

no debug mpls packets [interface]

Syntax Description

interface

(Optional) The interface or subinterface name.


Defaults

The debug output displays all labeled packets, regardless of the interface.

Command Modes

Privileged EXEC

Command History

Release
Modification

11.1CT

This command was introduced.

12.1(3)T

This command was modified for new MPLS terminology and syntax.

12.2(25)S

The command ouput was enhanced to display MPLS high availability information.

12.2(28)SB

This command was integrated into Cisco IOS Release 12.2(28)SB and implemented on the Cisco 10000 series routers.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Usage Guidelines

The optional interface parameter restricts the display to only those packets received or sent on the indicated interface or subinterface.


Note Use this command with care because it generates output for every packet processed. Furthermore, enabling this command causes fast and distributed label switching to be disabled for the selected interfaces. To avoid adversely affecting other system activity, use this command only when traffic on the network is at a minimum.


Examples

The following is sample output from the debug mpls packets command:

Router# debug mpls packets

TAG: Hs3/0: recvd: CoS=0, TTL=254, Tag(s)=27
TAG: Hs0/0: xmit: (no tag)

TAG: Hs0/0: recvd: CoS=0, TTL=254, Tag(s)=30
TAG: Hs3/0: xmit: CoS=0, TTL=253, Tag(s)=27

Table 3 describes the significant fields shown in the display.

Table 3 debug mpls packets Field Descriptions  

Field
Description

Hs0/0

The identifier for the interface on which the packet was received or sent.

recvd

Packet received.

xmit

Packet transmitted.

CoS

Class of Service field from the packet label header.

TTL

Time to live field from the packet label header.

(no tag)

Last label was popped off the packet and sent unlabeled.

Tag(s)

A list of labels on the packet, ordered from the top of the stack to the bottom.


Cisco 10000 Series Example

The following is sample output from the debug mpls packets command:

Router# debug mpls packets

Gi6/0/0: rx: Len 118 Stack {30 6 255} - ipv4 data
Gi6/1/1: tx: Len 118 Stack {22 6 254} - ipv4 data

Related Commands

Command
Description

show mpls forwarding-table

Displays the contents of the MPLS forwarding table.


mpls mtu

To set the per-interface Multiprotocol Label Switching (MPLS) maximum transmission unit (MTU) for labeled packets, use the mpls mtu command in interface configuration mode. To restore the default, use the no form of this command.

mpls mtu [override] bytes

no mpls mtu

Syntax Description

override

(Optional) Allows you to set the MPLS MTU value higher than the interface MTU value on interfaces (such as Ethernet) that have a default interface MTU value of 1580 or less. The override keyword is not available for interface types that do not have a default MTU value of 1580 or less.

Note The override keyword is supported in Cisco IOS Release 12.2(27)SBC and later releases.

bytes

The MTU in bytes includes the label stack in the value.


Defaults

The default MPLS MTU is the MTU configured for the interface.

Command Modes

Interface configuration

Command History

Release
Modification

11.1CT

This command was introduced.

12.1(3)T

This command was modified to incorporate new MPLS terminology.

12.2(25)S

The command changed the maximum allowable MPLS MTU values. See the "Usage Guidelines for Cisco IOS Release 12.2(25)S" section for more information.

12.2(27)SBC

The command changed so that you cannot set the MPLS MTU value larger than the interface MTU value. The override keyword was introduced. See the "Usage Guidelines for Cisco IOS Release 12.2(27)SBC and Later Releases" section for more information.

12.(28)SB

This command was integrated into Cisco IOS Release 12.2(28)SB.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Usage Guidelines

Usage Guidelines for Cisco IOS Release 12.2(25)S

If the interface MTU is less than 1524 bytes, you can set the maximum MPLS MTU to 24 bytes more than the interface MTU. For example, if the interface MTU is set to 1510 bytes, then you can set the maximum MPLS MTU to 1534 bytes (1510 + 24).


Note Although you can set the MPLS MTU to a value greater than the MPLS MTU, it is recommended that you keep the MPLS MTU less than or equal to the interface MTU to prevent the hardware from dropping packets. A best practice is to set the interface MTU of the core-facing interface to a value greater than either the IP MTU or interface MTU of the edge-facing interface.


If the interface MTU is greater than or equal to 1524 bytes, then you can set the maximum MPLS MTU as high as the interface MTU. For example, if the interface MTU is set to 1600 bytes, then you can set the MPLS MTU to a maximum of 1600 bytes. If you set the MPLS MTU higher than the interface MTU, traffic is dropped.

For interfaces that do not allow you to configure the interface MTU value and the interface MTU is
1500 bytes, the MPLS MTU range is 64 to 1524 bytes.

If you upgrade to Cisco IOS Release 12.2(25)S from an earlier release and you have an MPLS MTU setting that does not conform to these guidelines, the MPLS MTU setting is not accepted by the system. If this happens, reconfigure the MPLS MTU setting to conform to the guidelines.

Usage Guidelines for Cisco IOS Release 12.2(27)SBC and Later Releases

In Cisco IOS Releases 12.2(27)SBC and later releases, you cannot set the MPLS MTU value larger than the interface MTU value:

If you attempt to set the MPLS MTU value higher than the interface MTU value, the software displays the following error, which reminds you to set the interface MTU to a higher value before you set the MPLS MTU value:

% Please increase interface mtu to xxxx and then set mpls mtu

If you have an interface with a default interface MTU value of 1580 or less (such as an Ethernet interface), the mpls mtu command provides the override keyword, which allows you to set the MPLS MTU value higher than the interface MTU value. The override keyword is not available for interface types that do not have a default interface MTU value of 1580 or less.


Note The override keyword is supported in Cisco IOS Releases 12.2(27)SBC and 12.2(28)SB and later releases.


If you have configuration files with MPLS MTU values that are larger than the interface MTU values and you upgrade to Cisco IOS Release 12.2(27)SBC or a later release, the software does not change the MPLS MTU value. When you reboot the router, the software accepts whatever values are set for the MPLS MTU and the interface MTU. However, it is recommended that you make the MPLS MTU values lower than the interface MTU values. The following error message is displayed during system initialization:

Setting the mpls mtu to xxxx on interface x/x, which is higher than the interface MTU 
xxxx. This could lead to packet forwarding problems including packet drops. 

Changing the interface MTU can also modify the IP MTU, Connectionless Network Service (CLNS) MTU, and other MTU values, if they depend on the value of the interface MTU. The Open Shortest Path First (OSPF) routing protocol requires that the IP MTU values match on both ends of the link. Similarly, the Intermediate System-to-Intermediate System (IS-IS) routing protocol requires that the CLNS MTU values match on both ends of the link. If the values on both ends of the link do not match, IS-IS or OSPF cannot complete its initialization.

General Usage Guidelines

ATM interfaces cannot accommodate packets that exceed the Segmentation and Reassembly (SAR) buffer size, because labels are added to the packet. The bytes argument refers to the number of bytes in the packet before the addition of any labels. If each label is 4 bytes, the maximum value of bytes on an ATM interface is the physical MTU minus 4*x bytes, where x is the number of labels expected in the received packet.

If a labeled IPv4 packet exceeds the MPLS MTU size for the interface, Cisco IOS software fragments the packet. If a labeled non-IPv4 packet exceeds the MPLS MTU size, the packet is dropped.

All devices on a physical medium must have the same MPLS MTU value in order for MPLS to interoperate.

The MTU for labeled packets for an interface is determined as follows:

If the mpls mtu bytes command has been used to configure an MPLS MTU, the MTU for labeled packets is the bytes value.

Otherwise, the MTU for labeled packets is the default MTU for the interface.

Because labeling a packet makes it larger due to the label stack, you may want the MPLS MTU to be larger than the interface MTU or IP MTU in order to prevent the fragmentation of labeled packets, which would not be fragmented if they were unlabeled. In Cisco IOS Release 12.2(25)S and later releases, the MPLS MTU cannot be larger than the interface MTU.

Changing the interface MTU value (using the mtu interface configuration command) can affect the MPLS MTU of the interface. If the MPLS MTU value is the same as the interface MTU value (this is the default), and you change the interface MTU value, the MPLS MTU value will automatically be set to this new MTU as well. However, the reverse is not true; changing the MPLS MTU value has no effect on the interface MTU.

Examples

The following commands set the interface MTU value and MPLS MTU value for a serial interface:

interface Serial4/0
 mtu 1520
 ip unnumbered Loopback0
 mpls mtu 1510
 mpls traffic-eng tunnels
 mpls ip
 serial restart-delay 0
 ip rsvp bandwidth 2000 2000

The following example sets the maximum labeled packet size for the FastEthernet interface to 1508, which is common in an MPLS core carrying MPLS Virtual Private Network (VPN) traffic:

interface Fastethernet0
  mpls mtu override 1508

Related Commands

Command
Description

mtu

Sets the MTU size for the interface.


show atm vc

To display all ATM permanent virtual circuits (PVCs) and switched virtual circuits (SVCs) and traffic information, use the show atm vc command in privileged EXEC mode.

show atm vc [vcd | interface interface-number]

Syntax Description

vcd

(Optional) Specifies the virtual circuit descriptor (VCD) about which to display information.

interface interface-number

(Optional) Interface number or subinterface number of the PVC or SVC. Displays all PVCs and SVCs on the specified interface or subinterface.

The interface-number uses one of the following formats, depending on what router platform you are using:

For the ATM Interface Processor (AIP) on Cisco 7500 series routers; for the ATM port adapter, ATM-CES port adapter, and enhanced ATM port adapter on Cisco 7200 series routers; for the 1-port ATM-25 network module on Cisco 2600 and 3600 series routers: slot/0[.subinterface-number multipoint]

For the ATM port adapter and enhanced ATM port adapter on Cisco 7500 series routers: slot/port-adapter/0[.subinterface-number multipoint]

For the network processing module (NPM) on Cisco 4500 and Cisco 4700 routers: number[.subinterface-number multipoint]

For a description of these arguments, refer to the interface atm command.


Command Modes

Privileged EXEC

Command History

Release
Modification

10.0

This command was introduced.

11.1CA

Information about VCs on an ATM-CES port adapter was added to the command output.

12.0(5)T

Information about VCs on an extended Multiprotocol Label Switching (MPLS) ATM interface was added to the command output.

12.2(25)S

Information about packet drops and errors was added to the command output.

12.2(28)SB

This command was integrated into Cisco IOS Release 12.2(28)SB and implemented on the Cisco 10000 series routers.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Usage Guidelines

If no value is specified for the vcd argument, the command displays information for all PVCs and SVCs. The output is in summary form (one line per virtual circuit).

VCs on the extended MPLS ATM interfaces do not appear in the show atm vc command output. Instead, the show xtagatm vc command provides a similar output that shows information only on extended MPLS ATM VCs.

Examples

The following is sample output from the show atm vc command when no vcd value is specified. The status field is either ACTIVE or INACTIVE.

Router# show atm vc

Interface     VCD   VPI   VCI Type  AAL/Encaps     Peak   Avg.  Burst Status
ATM2/0          1     0     5  PVC  AAL5-SAAL     155000 155000    93 ACTIVE
ATM2/0.4        3     0    32  SVC  AAL5-SNAP     155000 155000    93 ACTIVE
ATM2/0.65432   10    10    10  PVC  AAL5-SNAP     100000  40000    10 ACTIVE
ATM2/0         99     0    16  PVC  AAL5-ILMI     155000 155000    93 ACTIVE
ATM2/0.105    250    33    44  PVC  AAL5-SNAP     155000 155000    93 ACTIVE
ATM2/0.100    300    22    33  PVC  AAL5-SNAP     155000 155000    93 ACTIVE
ATM2/0.12345 2047   255 65535  PVC  AAL5-SNAP         56     28  2047 ACTIVE

The following is sample output from the show atm vc command when a vcd value is specified for a circuit emulation service (CES) circuit:

Router# show atm vc 2

ATM6/0: VCD: 2, VPI: 10, VCI: 10
PeakRate: 2310, Average Rate: 2310, Burst Cells: 94
CES-AAL1, etype:0x0, Flags: 0x20138, VCmode: 0x0
OAM DISABLED
InARP DISABLED
OAM cells received: 0
OAM cells sent: 334272
Status: ACTIVE

The following is sample output from the show atm vc command when a vcd value is specified, displaying statistics for that virtual circuit only:

Router# show atm vc 8

ATM4/0: VCD: 8, VPI: 8, VCI: 8
PeakRate: 155000, Average Rate: 155000, Burst Cells: 0
AAL5-LLC/SNAP, etype:0x0, Flags: 0x30, VCmode: 0xE000
OAM frequency: 0 second(s)
InARP frequency: 1 minute(s)
InPkts: 181061, OutPkts: 570499, InBytes: 757314267, OutBytes: 2137187609
InPRoc: 181011, OutPRoc: 10, Broadcasts: 570459
InFast: 39, OutFast: 36, InAS: 11, OutAS: 6
OAM cells received: 0
OAM cells sent: 0
Status: UP

The following is sample output from the show atm vc command when a vcd value is specified, AAL3/4 is enabled, an ATM Switched Multimegabit Data Service (SMDS) subinterface has been defined, and a range of message identifier numbers (MIDs) has been assigned to the PVC:

Router# show atm vc 1

ATM4/0.1: VCD: 1, VPI: 0, VCI: 1
PeakRate: 0, Average Rate: 0, Burst Cells: 0
AAL3/4-SMDS, etype:0x1, Flags: 0x35, VCmode: 0xE200
MID start: 1, MID end: 16
InPkts: 0, OutPkts: 0, InBytes: 0, OutBytes: 0
InPRoc: 0, OutPRoc: 0, Broadcasts: 0
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0

The following is sample output from the show atm vc command when a vcd value is specified and generation of Operation, Administration, and Maintenance (OAM) F5 loopback cells has been enabled:

Router# show atm vc 7

ATM4/0: VCD: 7, VPI: 7, VCI: 7 
PeakRate: 0, Average Rate: 0, Burst Cells: 0
AAL5-LLC/SNAP, etype:0x0, Flags: 0x30, VCmode: 0xE000
OAM frequency: 10 second(s)
InARP DISABLED
InPkts: 0, OutPkts: 0, InBytes: 0, OutBytes: 0
InPRoc: 0, OutPRoc: 0, Broadcasts: 0
InFast:0, OutFast:0, InAS:0, OutAS:0
OAM cells received: 0
OAM cells sent: 1
Status: UP

The following is sample output from the show atm vc command when a vcd value is specified, and there is an incoming multipoint virtual circuit:

Router# show atm vc 3

ATM2/0: VCD: 3, VPI: 0, VCI: 33
PeakRate: 0, Average Rate: 0, Burst Cells: 0
AAL5-MUX, etype:0x809B, Flags: 0x53, VCmode: 0xE000
OAM DISABLED
InARP DISABLED
InPkts: 6646, OutPkts: 0, InBytes: 153078, OutBytes: 0
InPRoc: 6646, OutPRoc: 0, Broadcasts: 0
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
interface =  ATM2/0, call remotely initiated, call reference = 18082
vcnum = 3, vpi = 0, vci = 33, state = Active
 aal5mux vc, multipoint call
Retry count: Current = 0, Max = 10
timer currently inactive, timer value = never
Root Atm Nsap address: DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12

The following is sample output from the show atm vc command when a vcd value is specified, and there is an outgoing multipoint virtual circuit:

Router# show atm vc 6

ATM2/0: VCD: 6, VPI: 0, VCI: 35
PeakRate: 0, Average Rate: 0, Burst Cells: 0
AAL5-MUX, etype:0x800, Flags: 0x53, VCmode: 0xE000
OAM DISABLED
InARP DISABLED
InPkts: 0, OutPkts: 818, InBytes: 0, OutBytes: 37628
InPRoc: 0, OutPRoc: 0, Broadcasts: 818
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
interface =  ATM2/0, call locally initiated, call reference = 3
vcnum = 6, vpi = 0, vci = 35, state = Active
 aal5mux vc, multipoint call
Retry count: Current = 0, Max = 10
timer currently inactive, timer value = never
Leaf Atm Nsap address: DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12
Leaf Atm Nsap address: CD.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12

The following is sample output from the show atm vc command when a vcd value is specified and there is a PPP-over-ATM connection:

Router# show atm vc 1

ATM8/0.1: VCD: 1, VPI: 41, VCI: 41
PeakRate: 155000, Average Rate: 155000, Burst Cells: 96
AAL5-CISCOPPP, etype:0x9, Flags: 0xC38, VCmode: 0xE000
virtual-access: 1, virtual-template: 1
OAM DISABLED
InARP DISABLED
InPkts: 13, OutPkts: 10, InBytes: 198, OutBytes: 156
InPRoc: 13, OutPRoc: 10, Broadcasts: 0
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
OAM cells received: 0
OAM cells sent: 0

The following is sample output from the show atm vc command for IP multicast virtual circuits. The display shows the leaf count for multipoint VCs opened by the root. VCD 3 is a root of a multipoint VC with three leaf routers. VCD 4 is a leaf of some other router's multipoint VC. VCD 12 is a root of a multipoint VC with only one leaf router.

Router# show atm vc

            VCD/                                Peak     Avg/Min     Burst
Interface   Name  VPI   VCI   Type     Encaps      Kbps    Kbps      Cells         Sts
0/0         1       0     5    PVC      SAAL     155000  155000       96           UP
0/0         2       0    16    PVC      ILMI     155000  155000       96           UP
0/0         3       0   124 MSVC-3      SNAP     155000  155000       96           UP
0/0         4       0   125   MSVC      SNAP     155000  155000       96           UP
0/0         5       0   126   MSVC      SNAP     155000  155000       96           UP
0/0         6       0   127   MSVC      SNAP     155000  155000       96           UP
0/0         9       0   130   MSVC      SNAP     155000  155000       96           UP
0/0         10      0   131    SVC      SNAP     155000  155000       96           UP
0/0         11      0   132 MSVC-3      SNAP     155000  155000       96           UP
0/0         12      0   133 MSVC-1      SNAP     155000  155000       96           UP
0/0         13      0   134    SVC      SNAP     155000  155000       96           UP
0/0         14      0   135 MSVC-2      SNAP     155000  155000       96           UP
0/0         15      0   136 MSVC-2      SNAP     155000  155000       96           UP

The following is sample output from the show atm vc command for an IP multicast virtual circuit. The display shows the owner of the VC and leaves of the multipoint VC. This VC was opened by IP multicast. The three leaf routers' ATM addresses are included in the display. The VC is associated with IP group address 10.1.1.1.

Router# show atm vc 11

ATM0/0: VCD: 11, VPI: 0, VCI: 132
PeakRate: 155000, Average Rate: 155000, Burst Cells: 96
AAL5-LLC/SNAP, etype:0x0, Flags: 0x650, VCmode: 0xE000
OAM DISABLED
InARP DISABLED
InPkts: 0, OutPkts: 12, InBytes: 0, OutBytes: 496
InPRoc: 0, OutPRoc: 0, Broadcasts: 12
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
OAM cells received: 0
OAM cells sent: 0
Status: ACTIVE, TTL: 2, VC owner: IP Multicast (10.1.1.1)
interface =  ATM0/0, call locally initiated, call reference = 2
vcnum = 11, vpi = 0, vci = 132, state = Active
 aal5snap vc, multipoint call
Retry count: Current = 0, Max = 10
timer currently inactive, timer value = 00:00:00
Leaf Atm Nsap address: 47.0091810000000002BA08E101.444444444444.02 
Leaf Atm Nsap address: 47.0091810000000002BA08E101.333333333333.02 
Leaf Atm Nsap address: 47.0091810000000002BA08E101.222222222222.02 

The following is sample output from the show atm vc command where no VCD is specified and private VCs are present:

Router# show atm vc

AAL /         Peak   Avg.  Burst       
Interface     VCD   VPI   VCI Type  Encapsulation  Kbps   Kbps  Cells Status
ATM1/0          1     0    40  PVC  AAL5-SNAP          0      0     0 ACTIVE  
ATM1/0          2     0    41  PVC  AAL5-SNAP          0      0     0 ACTIVE  
ATM1/0          3     0    42  PVC  AAL5-SNAP          0      0     0 ACTIVE  
ATM1/0          4     0    43  PVC  AAL5-SNAP          0      0     0 ACTIVE  
ATM1/0          5     0    44  PVC  AAL5-SNAP          0      0     0 ACTIVE  
ATM1/0         15     1    32  PVC  AAL5-XTAGATM       0      0     0 ACTIVE  
ATM1/0         17     1    34  TVC  AAL5-XTAGATM       0      0     0 ACTIVE  
ATM1/0         26     1    43  TVC  AAL5-XTAGATM       0      0     0 ACTIVE  
ATM1/0         28     1    45  TVC  AAL5-XTAGATM       0      0     0 ACTIVE  
ATM1/0         29     1    46  TVC  AAL5-XTAGATM       0      0     0 ACTIVE  
ATM1/0         33     1    50  TVC  AAL5-XTAGATM       0      0     0 ACTIVE 

When you specify a VCD value and the VCD corresponds to that of a private VC on a control interface, the display output appears as follows:

Router# show atm vc 15

ATM1/0 33     1    50  TVC  AAL5-XTAGATM       0      0     0 ACTIVE 
ATM1/0: VCD: 15, VPI: 1, VCI: 32, etype:0x8, AAL5 - XTAGATM, Flags: 0xD38
PeakRate: 0, Average Rate: 0, Burst Cells: 0, VCmode: 0x0 
XTagATM1, VCD: 1, VPI: 0, VCI: 32 
OAM DISABLED, InARP DISABLED 
InPkts: 38811, OutPkts: 38813, InBytes: 2911240, OutBytes: 2968834 
InPRoc: 0, OutPRoc: 0, Broadcasts: 0 
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0 
OAM F5 cells sent: 0, OAM cells received: 0 
Status: ACTIVE

Table 4 describes the fields shown in the displays.

Table 4 show atm vc Field Descriptions 

Field
Description

Interface

Interface slot and port.

VCD/Name

Virtual circuit descriptor (virtual circuit number). The connection name is displayed if the VC was configured using the pvc command and the name was specified.

VPI

Virtual path identifier.

VCI

Virtual channel identifier.

Type

Type of virtual circuit, either PVC, SVC, TVC, or multipoint SVC (MSVC).

MSVC (with no -x ) indicates that VCD is a leaf of some other router's multipoint VC.

MSVC-x indicates there are x leaf routers for that multipoint VC opened by the root.

Type of PVC detected from PVC discovery, either PVC-D, PVC-L, or PVC-M.

PVC-D indicates a PVC created due to PVC discovery.

PVC-L indicates that the corresponding peer of this PVC could not be found on the switch.

PVC-M indicates that some or all of the Quality of Service (QoS) parameters of this PVC do not match those of the corresponding peer on the switch.

TVC indicates a Tag virtual circuit.

Encaps

Type of ATM adaptation layer (AAL) and encapsulation.

PeakRate

Kilobits per second sent at the peak rate.

Average Rate

Kilobits per second sent at the average rate.

Burst Cells

Value that equals the maximum number of ATM cells the virtual circuit can send at peak rate.

Status

Status of the VC connection.

UP indicates that the connection is enabled for data traffic.

DOWN indicates that the connection is not ready for data traffic. When the Status field is DOWN, a State field is shown.

INACTIVE indicates that the interface is down.

ACTIVE indicates that the interface is in use and active.

etype

Encapsulation type.

Flags

Bit mask describing virtual circuit information. The flag values are summed to result in the displayed value.

0x10000 ABR VC
0x20000 CES VC
0x40000 TVC
0x100 TEMP (automatically created)
0x200 MULTIPOINT
0x400 DEFAULT_RATE
0x800 DEFAULT_BURST
0x10 ACTIVE
0x20 PVC
0x40 SVC
0x0 AAL5-SNAP
0x1 AAL5-NLPID
0x2 AAL5-FRNLPID
0x3 AAL5-MUX
0x4 AAL3/4-SMDS
0x5 QSAAL
0x6 AAL5-ILMI
0x7 AAL5-LANE
0x8 AAL5-XTAGATM
0x9 CES-AAL1
0xA F4-OAM

VCmode

AIP-specific or NPM-specific register describing the usage of the virtual circuit. This register contains values such as rate queue, peak rate, and AAL mode, which are also displayed in other fields.

OAM frequency

Seconds between OAM loopback messages, or DISABLED if OAM is not in use on this VC.

InARP frequency

Minutes between Inverse Address Resolution Protocol (InARP) messages, or DISABLED if InARP is not in use on this VC.

virtual-access

Virtual access interface identifier.

virtual-template

Virtual template identifier.

InPkts

Total number of packets received on this virtual circuit. This number includes all fast-switched and process-switched packets.

OutPkts

Total number of packets sent on this virtual circuit. This number includes all fast-switched and process-switched packets.

InBytes

Total number of bytes received on this virtual circuit. This number includes all fast-switched and process-switched packets.

OutBytes

Total number of bytes sent on this virtual circuit. This number includes all fast-switched and process-switched packets.

InPRoc

Number of process-switched input packets.

OutPRoc

Number of process-switched output packets.

Broadcasts

Number of process-switched broadcast packets.

InFast

Number of fast-switched input packets.

OutFast

Number of fast-switched output packets.

InAS

Number of autonomous-switched or silicon-switched input packets.

OutAS

Number of autonomous-switched or silicon-switched output packets.

OAM cells received

Number of OAM cells received on this virtual circuit.

OAM cells sent

Number of OAM cells sent on this virtual circuit.

TTL

Time to live in ATM hops across the VC.

VC owner

IP Multicast address of the group.


Related Commands

Command
Description

atm nsap-address

Sets the NSAP address for an ATM interface using SVC mode.

show xtagatm vc

Displays information about the VCs on the extended MPLS ATM interfaces.


show mpls forwarding-table

To display the contents of the Multiprotocol Label Switching (MPLS) Label Forwarding Information Base (LFIB), use the show mpls forwarding-table command in privileged EXEC mode.

show mpls forwarding-table [network {mask | length} | labels label [- label] | interface interface | next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]

Syntax Description

network

(Optional) Destination network number.

mask

IP address of the destination mask whose entry is to be shown.

length

Number of bits in the mask of the destination.

labels label - label

(Optional) Displays only entries with the specified local labels.

interface interface

(Optional) Displays only entries with the specified outgoing interface.

next-hop address

(Optional) Displays only entries with the specified neighbor as the next hop.

lsp-tunnel

(Optional) Displays only entries with the specified label switched path (LSP) tunnel, or with all LSP tunnel entries.

tunnel-id

(Optional) Specifies the LSP tunnel for which to display entries.

vrf vrf-name

(Optional) Displays only entries with the specified VPN routing and forwarding (VRF) instance.

detail

(Optional) Displays information in long form (includes length of encapsulation, length of MAC string, maximum transmission unit (MTU), and all labels).


Command Modes

Privileged EXEC

Command History

Release
Modification

11.1CT

This command was introduced.

12.1(3)T

This command was updated with MPLS terminology and command syntax.

12.2(8)T

The command was modified to accommodate use of the MPLS experimental (EXP) level as a selection criterion for packet forwarding. The output display was modified to include a bundle adjacency field and exp (vcd) values when the optional detail keyword is specified.

12.0(22)S

IPv6 MPLS aggregate label and prefix information was added to the display.

12.2(14)S

This command was integrated into Cisco IOS Release 12.2(14)S.

12.0(27)S

The command output was modified to include explicit-null label information.

12.2(25)S

The output was changed in the following ways:

The term "tag" was replaced with the term "label."

The term "untagged" was replaced with the term "no label."

12.0(29)S

This command was integrated into Cisco IOS Release 12.0(29)S.

12.2(28)SB

This command was integrated into Cisco IOS Release 12.2(28)SB and implemented on the Cisco 10000 series routers.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Examples

The following is sample output from the show mpls forwarding-table command:

Router# show mpls forwarding-table

Local Outgoing      Prefix            Bytes label Outgoing       Next Hop       
Label Label or VC   or Tunnel Id      switched  interface                     
26    No Label      10.253.0.0/16     0         Et4/0/0       10.27.32.4    
28    1/33          10.15.0.0/16      0         AT0/0.1       point2point    
29    Pop Label     10.91.0.0/16      0         Hs5/0         point2point    
      1/36          10.91.0.0/16      0         AT0/0.1       point2point    
30    32            10.250.0.97/32    0         Et4/0/2       10.92.0.7      
      32            10.250.0.97/32    0         Hs5/0         point2point    
34    26            10.77.0.0/24      0         Et4/0/2       10.92.0.7      
      26            10.77.0.0/24      0         Hs5/0         point2point    
35    No Label[T]   10.100.100.101/32 0         Tu301         point2point    
36    Pop Label     10.1.0.0/16      0         Hs5/0         point2point    
      1/37          10.1.0.0/16      0         AT0/0.1       point2point    

[T]     Forwarding through a TSP tunnel.
        View additional labeling info with the 'detail' option

The following is sample output from the show mpls forwarding-table command when the IPv6 Provider Edge Router over MPLS feature is configured to allow IPv6 traffic to be transported across an IPv4 MPLS backbone. The labels are aggregated because there are several prefixes for one local label, and the prefix column contains "IPv6" instead of a target prefix.

Router# show mpls forwarding-table

Local Outgoing      Prefix            Bytes label Outgoing       Next Hop       
Label Label or VC   or Tunnel Id      switched  interface                     
16    Aggregate     IPv6              0             
17    Aggregate     IPv6              0                 
18    Aggregate     IPv6              0                 
19    Pop Label     192.168.99.64/30  0         Se0/0         point2point    
20    Pop Label     192.168.99.70/32  0         Se0/0         point2point      
21    Pop Label     192.168.99.200/32 0         Se0/0         point2point    
22    Aggregate     IPv6              5424    
23    Aggregate     IPv6              3576 
24    Aggregate     IPv6              2600

The following is sample output from the show mpls forwarding-table command when you specify the detail keyword. If the MPLS EXP level is used as a selection criterion for packet forwarding, a bundle adjacency exp (vcd) field is included in the display. This field includes the EXP value and the corresponding virtual circuit descriptor (VCD) in parentheses. The line in the output that reads "No output feature configured" indicates that the MPLS egress NetFlow accounting feature is not enabled on the outgoing interface for this prefix.

Router# show mpls forwarding-table detail

Local Outgoing      Prefix            Bytes label Outgoing       Next Hop       
label   label or VC     or Tunnel Id      switched  interface                     
16    Pop label       10.0.0.6/32        0         AT1/0.1       point2point 
  Bundle adjacency exp(vcd)
  0(1) 1(1) 2(1) 3(1) 4(1) 5(1) 6(1) 7(1)
  MAC/Encaps=12/12, MTU=4474, label Stack{}
      00010000AAAA030000008847
  No output feature configured
17    18            10.0.0.9/32        0         AT1/0.1       point2point    
  Bundle adjacency exp(vcd)
  0(1) 1(1) 2(1) 3(1) 4(1) 5(1) 6(1) 7(1)
  MAC/Encaps=12/16, MTU=4470, label Stack{18}
      00010000AAAA030000008847 00012000
  No output feature configured
18    19            10.0.0.10/32        0        AT1/0.1       point2point    
  Bundle adjacency exp(vcd)
  0(1) 1(1) 2(1) 3(1) 4(1) 5(1) 6(1) 7(1)
  MAC/Encaps=12/16, MTU=4470, label Stack{19}
      00010000AAAA030000008847 00013000
  No output feature configured
19    17            10.0.0.0/8         0        AT1/0.1       point2point    
  Bundle adjacency exp(vcd)
  0(1) 1(1) 2(1) 3(1) 4(1) 5(1) 6(1) 7(1)
  MAC/Encaps=12/16, MTU=4470, label Stack{17}
      00010000AAAA030000008847 00011000
  No output feature configured
20    20            10.0.0.0/8         0        AT1/0.1       point2point    
  Bundle adjacency exp(vcd)
  0(1) 1(1) 2(1) 3(1) 4(1) 5(1) 6(1) 7(1)
  MAC/Encaps=12/16, MTU=4470, label Stack{20}
      00010000AAAA030000008847 00014000
  No output feature configured
21    Pop label       10.0.0.0/24        0        AT1/0.1       point2point 
  Bundle adjacency exp(vcd)
  0(1) 1(1) 2(1) 3(1) 4(1) 5(1) 6(1) 7(1)
  MAC/Encaps=12/12, MTU=4474, label Stack{}
      00010000AAAA030000008847
  No output feature configured
22    Pop label       10.0.0.4/32         0        Et2/3         10.0.0.4 
  MAC/Encaps=14/14, MTU=1504, label Stack{}
      000427AD10430005DDFE043B8847
  No output feature configured

The following is sample output from the show mpls forwarding-table command when you use the detail keyword. In this example, the MPLS egress NetFlow accounting feature is enabled on the first three prefixes, as indicated by the line in the output that reads "Feature Quick flag set."

Router# show mpls forwarding-table detail

Local  Outgoing    Prefix            Bytes label  Outgoing   Next Hop
label    label or VC   or Tunnel Id      switched   interface
16     Aggregate   10.0.0.0/8[V]     0
        MAC/Encaps=0/0, MTU=0, label Stack{}
        VPN route: vpn1
        Feature Quick flag set
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 
17     No label    10.0.0.0/8[V]      0          Et0/0/2    10.0.0.1
        MAC/Encaps=0/0, MTU=1500, label Stack{}
        VPN route: vpn1
        Feature Quick flag set
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
18     No label    10.42.42.42/32[V] 4185       Et0/0/2    10.0.0.1
        MAC/Encaps=0/0, MTU=1500, label Stack{}
        VPN route: vpn1
        Feature Quick flag set
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
19     2/33        10.41.41.41/32    0          AT1/0/0.1  point2point
        MAC/Encaps=4/8, MTU=4470, label Stack{2/33(vcd=2)}
        00028847 00002000
        No output feature configured

Cisco 10000 Series Examples

The following is sample output from the show mpls forwarding-table command:

Router# show mpls forwarding-table

Local   Outgoing      Prefix            Bytes Label   Outgoing   Next Hop
Label   Label or VC   or Tunnel Id      Switched      interface
16      Pop Label     10.0.0.0/8        0             Fa1/0/0    10.0.0.2
        Pop Label     10.0.0.0/8        0             Fa1/1/0    10.0.0.2
17      Aggregate     10.0.0.0/8[V]     570           vpn2
21      Pop Label     10.11.11.11/32    0             Fa1/0/0    10.0.0.2
22      Pop Label     10.12.12.12/32    0             Fa1/1/0    10.0.0.2
23      No Label      10.3.0.0/16[V]     0             Fa4/1/0   10.0.0.2

The following is Cisco 10000 series sample output from the show mpls forwarding-table command when you specify the detail keyword:

Router# show mpls forwarding-table detail

Local   Outgoing      Prefix            Bytes Label   Outgoing   Next Hop
Label   Label or VC   or Tunnel Id      Switched      interface
16      Pop Label     10.0.0.0/8        0             Fa1/0/0    10.0.0.2
        MAC/Encaps=14/14, MRU=1500, Label Stack{}
        000B45C93889000B45C930218847
        No output feature configured
        Pop Label     10.0.0.0/8        0             Fa1/1/0     10.0.0.2
        MAC/Encaps=14/14, MRU=1500, Label Stack{}
        000B45C92881000B45C930288847
        No output feature configured
17      Aggregate    10.0.0.0/8[V]      570           vpn2
        MAC/Encaps=0/0, MRU=0, Label Stack{}
        VPN route: vpn2
        No output feature configured
21      Pop Label     10.11.11.11/32     0            Fa1/0/0     10.0.0.2
        MAC/Encaps=14/14, MRU=1500, Label Stack{}
       000B45C93889000B45C930218847
       No output feature configured

Table 5 describes the significant fields shown in the displays.

Table 5 show mpls forwarding-table Field Descriptions 

Field
Description

Local label

Label assigned by this router.

Outgoing Label or VC

Note VC is not applicable to the Cisco 10000 series routers.

Label assigned by the next hop or virtual path identifier (VPI)/virtual channel identifier (VCI) used to get to next hop. The entries in this column are the following:

[T]—Means forwarding through an LSP tunnel.

No Label—Means that there is no label for the destination from the next hop or that label switching is not enabled on the outgoing interface.

Pop Label—Means that the next hop advertised an implicit NULL label for the destination and that the router popped the top label.

Aggregate—Means there are several prefixes for one local label. This entry is used when IPv6 is configured on edge routers to transport IPv6 traffic over an IPv4 MPLS network.

Prefix or Tunnel Id

Address or tunnel to which packets with this label are sent.

Note If IPv6 is configured on edge routers to transport IPv6 traffic over an IPv4 MPLS network, "IPv6" is displayed here.

Bytes Label Switched

Number of bytes switched with this incoming label.

Outgoing interface

Interface through which packets with this label are sent.

Next Hop

IP address of the neighbor that assigned the outgoing label.

Bundle adjacency exp(vcd)

Bundle adjacency information. Includes the MPLS EXP value and the corresponding VCD.

MAC/Encaps

Length in bytes of the Layer 2 header and length in bytes of the packet encapsulation, including the Layer 2 header and label header.

MTU

MTU of the labeled packet.

Label Stack

All the outgoing labels. If the outgoing interface is transmission convergence (TC)-ATM, the VCD is also shown.

Note TC-ATM is not supported on Cisco 10000 series routers.

00010000AAAA030000008847 00013000

The actual encapsulation in hexadecimal form. A space is shown between Layer 2 and the label header.


Explicit-Null Label Example

The following example shows output, including the explicit-null label = 0 (commented in bold), from the show mpls forwarding-table command on a CSC-PE router:

Router# show mpls forwarding-table 

Local  Outgoing      Prefix            Bytes label  Outgoing   Next Hop    
label  label or VC   or Tunnel Id      switched     interface              
17     Pop label     10.10.0.0/32      0            Et2/0      10.10.0.1      
18     Pop label     10.10.10.0/24     0            Et2/0      10.10.0.1      
19     Aggregate     10.10.20.0/24[V]  0                                  
20     Pop label     10.10.200.1/32[V] 0            Et2/1      10.10.10.1      
21     Aggregate     10.10.1.1/32[V]   0                                  
22     0             192.168.101.101/32[V]   \
                                       0            Et2/1      192.168.101.101      
23     0             192.168.101.100/32[V]   \
                                       0            Et2/1      192.168.101.100      
25     0             192.168.102.125/32[V] 0        Et2/1      192.168.102.125 !outlabel 
value 0

Table 6 describes the significant fields shown in the display.

Table 6 show mpls forwarding-table Field Descriptions 

Field
Description

Local label

Label assigned by this router.

Outgoing label or VC

Label assigned by the next hop or VPI/VCI used to get to next hop. The entries this column are the following:

[T]—Means forwarding through an LSP tunnel.

No label—Means that there is no label for the destination from the next hop or that label switching is not enabled on the outgoing interface.

Pop label—Means that the next hop advertised an implicit NULL label for the destination and that this router popped the top label.

Aggregate—Means there are several prefixes for one local label. This entry is used when IPv6 is configured on edge routers to transport IPv6 traffic over an IPv4 MPLS network.

0—Means the explicit null label value = 0.

Prefix or Tunnel Id

Address or tunnel to which packets with this label are going.

Note If IPv6 is configured on edge routers to transport IPv6 traffic over an IPv4 MPLS network, IPv6 is displayed here.

Bytes label switched

Number of bytes switched with this incoming label.

Outgoing interface

Interface through which packets with this label are sent.

Next Hop

IP address of the neighbor that assigned the outgoing label.


Related Commands

Command
Description

neighbor send-label

Enables a BGP router to send MPLS labels with BGP routes to a neighboring BGP router.

neighbor send-label explicit-null

Enables a BGP router to send MPLS labels with explicit-null information for a CSC-CE router and BGP routes to a neighboring CSC-PE router.


show tech-support mpls

To generate a report of all Multiprotocol Label Switching (MPLS)-related information, use the show tech-support mpls command in privileged EXEC mode.

show tech-support mpls [vrf vrf-name]

Syntax Description

vrf vrf-name

(Optional) Displays MPLS information about the specified VPN routing and forwarding (VRF) instance.


Command Modes

Privileged EXEC

Command History

Release
Modification

12.2(25)S

This command was introduced.

12.2(28)SB

This command was integrated into Cisco IOS Release 12.2(28)SB and implemented on the Cisco 10000 series routers.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Usage Guidelines

This command is useful when you contact technical support personnel with questions regarding MPLS. The show tech-support mpls command generates a series of reports. The show tech-support mpls command is equivalent to issuing the following commands:

MPLS Forwarding Information Commands

show adjacency detail
show cef drop show cef events
show cef not-cef-switched
show cef state
show interface accounting | exclude sab
show interfaces statistic | exclude sabl
show ip cef adjacency discard
show ip cef adjacency drop
show ip cef adjacency glean
show ip cef adjacency null
show ip cef adjacency punt
show ip cef detail internal
show ip cef inconsistency
show ip cef summary
show ip cef unresolved internal
show ip interfaces
show ip route
show ip traffic
show mpls forwarding-table detail
show mpls interfaces all
show mpls interfaces all internal
show mpls label range
show mpls static binding

MPLS Forwarding: Cell Mode (LC-ATM) Commands


Note These commands are not supported on Cisco 10000 series routers.


show atm vc
show controller vsi descriptor
show controller vsi session
show controller vsi status
show XTagATM cross-connect
show XTagATM cross-connect traffic
show XTagATM vc

MPLS Forwarding: Quality of Service (QoS) Commands


Note These commands are not supported on Cisco 10000 series routers.


show interfaces fair-queue
show interfaces mpls-exp
show interfaces precedence

MPLS Label Distribution Protocol (LDP) Commands

show mpls atm-ldp bindings
show mpls atm-ldp bindwait
show mpls atm-ldp capability
show mpls atm-ldp summary            <=====
Not supported on Cisco 10000 series routers
show mpls ip binding detail
show mpls ldp backoff
show mpls ldp discovery all detail
show mpls ldp neighbor all
show mpls ldp neighbor detail
show mpls ldp parameters

MPLS LDP: Stateful Switchover/Nonstop Forwarding (SSO/NSF) Support and Graceful Restart Commands

show mpls checkpoint label-binding
show mpls ldp checkpoint
show mpls ldp graceful-restart
show mpls ldp neighbor graceful-restart

MPLS Traffic Engineering Commands

show ip ospf database opaque-area
show ip ospf database opaque-link
show ip ospf mpls traffic-eng fragment
show ip ospf mpls traffic-eng link
show ip rsvp fast-reroute detail
show ip rsvp installed
show ip rsvp interface
show ip rsvp neighbor
show ip rsvp reservation
show ip rsvp sender
show isis mpls traffic-eng adjacency-log
show isis mpls traffic-eng advertisements
show isis mpls traffic-eng tunnel
show mpls traffic-end link-management interfaces
show mpls traffic-eng autoroute
show mpls traffic-eng fast-reroute database detail
show mpls traffic-eng fast-reroute log reroutes
show mpls traffic-eng forwarding adjacency
show mpls traffic-eng link-management admission-control
show mpls traffic-eng link-management advertisements
show mpls traffic-eng link-management bandwidth-allocation
show mpls traffic-eng link-management summary
show mpls traffic-eng topology
show mpls traffic-eng tunnels
show mpls traffic-eng tunnels brief
show mpls traffic-eng tunnels statics summary

MPLS VPN Commands

show ip bgp labels
show ip bgp neighbors
show ip bgp vpnv4 all
show ip bgp vpnv4 all labels
show ip bgp vpnv4 all summary
show ip vrf detail
show ip vrf interfaces
show ip vrf select

Any Transport over MPLS (AToM) Commands

show mpls l2transport binding
show mpls l2transport hw-capability
show mpls l2transport summary
show mpls l2transport vc detail

MPLS VPN VRF-Specific Commands

show ip bgp vpnv4 vpn-name dampening flap-statistics
show ip bgp vpnv4
vpn-name labels
show ip bgp vpnv4
vpn-name peer-group
show ip bgp vpnv4
vpn-name summary
show ip bgp vpnv4 vrf
vpn-name neighbors
show ip vrf detail
vpn-name
show ip vrf interfaces vpn-name
show ip vrf select vpn-name

MPLS VPN VRF-Specific Forwarding Commands

show ip cef vrf vpn-name adjacency discard
show ip cef vrf
vpn-name adjacency drop
show ip cef vrf
vpn-name adjacency glean
show ip cef vrf
vpn-name adjacency null
show ip cef vrf
vpn-name adjacency punt
show ip cef vrf
vpn-name inconsistency
show ip cef vrf
vpn-name internal
show ip cef vrf
vpn-name summary
show ip route vrf
vpn-name
show ip vrf interfaces vpn-name
show mpls forwarding-table vrf vpn-name
show mpls interface vrfvpn-name detail

MPLS LDP VRF-Specific Commands

show mpls ip binding vrf vpn-name atm detail
show mpls ip binding vrf
vpn-name detail
show mpls ip binding vrf
vpn-name local
show mpls ip binding vrf
vpn-name summary
show mpls ldp discovery vrf
vpn-name detail
show mpls ldp neighbor vrf
vpn-name detail

MPLS LDP VRF Graceful Restart-Specific Commands

show mpls ldp neighbor vrf vpn-name graceful-restart


These commands are documented in individual feature modules or Cisco IOS Release 12.2 command references. Refer to the individual commands for information about the output these commands generate.

Examples

The following example displays an abbreviated version of the show tech-support mpls command output:

Router# show tech-support mpls 

------------------ show version ------------------

Cisco IOS Software, 7300 Software (C7300-P-M), Version 12.2(27)SBC, RELEASE SOF)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2005 by Cisco Systems, Inc.
Compiled Sat 10-Sep-05 17:44 by ssearch
.
.
.
------------------ show running-config ------------------

Building configuration...

Current configuration : 1827 bytes
.
.
.
------------------ show mpls ldp graceful-restart ------------------

LDP Graceful Restart is disabled
Neighbor Liveness Timer: 120 seconds
Max Recovery Time: 120 seconds
Forwarding State Holding Time: 600 seconds

Related Commands

Command
Description

show tech-support

Displays the equivalent of the show buffers, show controllers, show interfaces, show process, show process memory, show running-config, show stacks, and show version commands.


Feature Information for MPLS High Availability: Command Changes

Table 7 lists the release history for this feature.

Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.

Cisco IOS software images are specific to a Cisco IOS software release, a feature set, and a platform. Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.


Note Table 7 lists only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.


Table 7 Feature Information for MPLS High Availability: Command Changes 

Feature Name
Releases
Feature Information

MPLS High Availability: Command Changes

12.2(25)S
12.2(28)SB
12.2(33)SRA
12.2(33)SXH

This feature explains the MPLS commands that have been modified for the MPLS High Availability feature.

In 12.2(25)S, this feature was introduced on the Cisco 7500 series router.

In 12.2(28)SB, support was added for the Cisco 10000 series router.

In 12.2(33)SRA, support was added for the Cisco 7600 series router.

In 12.2(33)SXH, this feature was integrated into Cisco IOS Release 12.2(33)SXH.