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Cisco IOS Software Releases 12.2 T

ATM SNMP Trap and OAM Enhancements

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Table Of Contents

ATM SNMP Trap and OAM Enhancements

Feature Overview

ATM PVC Up Trap

ATM PVC OAM Failure Trap

Extended ATM PVC Traps

Supported MIB Objects and Tables

Benefits

Restrictions

Related Documents

Supported Platforms

Supported Standards, MIBs, and RFCs

Prerequisites

Configuration Tasks

Configuring Extended ATM PVC Trap Support

Enabling OAM Management

Verifying ATM PVC Traps

Monitoring and Maintaining ATM PVC Traps

Configuration Examples

Configuring Extended ATM PVC Trap Support: Example

Extended ATM PVC Traps Output: Examples

Command Reference

snmp-server enable traps atm pvc extension

Glossary


ATM SNMP Trap and OAM Enhancements

Feature History

Release
Modification

12.2(4)T

This feature was introduced.

12.2(4)T3

Support for Cisco 7500 series routers was added.


This document describes the ATM SNMP Trap and OAM Enhancements feature in Cisco IOS Release 12.2(4)T. It includes the following sections:

•Feature Overview

•Supported Platforms

•Supported Standards, MIBs, and RFCs

•Prerequisites

•Configuration Tasks

•Monitoring and Maintaining ATM PVC Traps

•Configuration Examples

•Command Reference

•Glossary

Feature Overview

The ATM SNMP Trap and OAM Enhancements feature introduces the following enhancements to the Simple Network Management Protocol (SNMP) notifications for ATM permanent virtual circuits (PVCs) and to Operation, Administration, and Maintenance (OAM) functionality:

•ATM PVC traps will be generated when the operational state of a PVC changes from the DOWN to UP state.

•ATM PVC traps will be generated when OAM loopback fails. Additionally, when OAM loopback fails, the PVC will now remain in the UP state, rather than going down.

•The ATM PVC traps are now extended to include virtual path identifier/virtual channel indentifier (VPI/ VCI) information, the number of state transitions a PVC goes through in an interval, and the time stamp of the first and the last PVC state transition.

The ATM SNMP trap and OAM enhancements are described in the following sections:

•ATM PVC Up Trap

•ATM PVC OAM Failure Trap

•Extended ATM PVC Traps

•Supported MIB Objects and Tables

ATM PVC Up Trap

Before the introduction of the ATM SNMP trap and OAM enhancements, the only SNMP notifications for ATM PVCs were the ATM PVC failure traps, which were generated when a PVC failed or left the UP operational state. The ATM SNMP trap and OAM enhancements introduce ATM PVC up traps, which are generated when a PVC changes from the DOWN to the UP state.

ATM PVC OAM Failure Trap

The ATM SNMP trap and OAM enhancements introduce the ATM PVC OAM failure trap. OAM loopback is a mechanism that detects whether a connection is up or down by sending OAM end-to-end loopback command/response cells. An OAM loopback failure indicates that the PVC has lost connectivity. The ATM PVC OAM failure trap is generated when OAM loopback for a PVC fails and is sent at the end of the notification interval.

When OAM loopback for a PVC fails, the PVC is included in the atmStatusChangePVclRangeTable or atmCurrentStatusChangePVclTable and in the ATM PVC OAM failure trap.

Before the introduction of this feature, if OAM loopback failed, the PVC would be placed in the down state. When the ATM PVC OAM failure trap is enabled, the PVC remains up when OAM loopback fails so that the flow of data will still be possible.

Note ATM PVC traps are generated at the end of the notification interval. It is possible to generate all three types of ATM PVC traps (the ATM PVC failure trap, ATM PVC up trap, and ATM PVC OAM failure trap) at the end of the same notification interval; however, only one type of trap will be generated for each PVC.

Extended ATM PVC Traps

The ATM SNMP Trap and OAM Enhancements feature introduces extended ATM PVC traps. The extended traps include VPI/VCI information for affected PVCs, the number of up-to-down and down-to-up state transitions a PVC goes through in an interval, and the time stamp of the first and the last PVC state transition.

Note Extended ATM PVC traps cannot be used at the same time as the legacy ATM PVC trap. The legacy ATM PVC trap must be disabled by using the no snmp-server enable traps atm pvc command before extended ATM PVC traps can be configured.

Supported MIB Objects and Tables

The ATM PVC trap is defined in the ATM PVC trap MIB. The ATM SNMP trap and OAM enhancements introduce the following MIB objects and tables:

•The table atmInterfaceExt2Table displays the status of ATM PVCs and is indexed by ifIndex. This table contains the following objects:

–atmIntfCurrentlyDownToUpPVcls

–atmIntfOAMFailedPVcls

–atmIntfCurrentlyOAMFailingPVcls

•The table atmCurrentStatusChangePVclTable displays information about ATM PVCs that have gone through an operational state change and is indexed by ifIndex, atmVclVpi, and atmVclVci. This table contains the following objects:

–atmPVclStatusTransition

–atmPVclStatusChangeStart

–atmPVclStatusChangeEnd

•The table atmStatusChangePVclRangeTable displays information about ATM PVC ranges and is indexed by ifIndex, atmVclVpi, and rangeIndex. This table contains the following objects:

–atmPVclLowerRangeValue

–atmPVclHigherRangeValue

–atmPVclRangeStatusChangeStart

–atmPVclRangeStatusChangeEnd

•The ATM PVC Up Trap "atmIntfPvcUpTrap" contains the following objects:

–ifIndex

–atmIntfCurrentlyDownToUpPVcls

•The ATM PVC OAM Failure Trap "atmIntfPvcOAMFailureTrap" contains the following objects:

–ifIndex

–atmIntfOAMFailedPVcls

–atmIntfCurrentlyOAMFailingPVcls

For a complete description of the extended ATM PVC MIB, see the MIB file called CISCO-IETF-ATM2-PVCTRAP-MIB-EXTN.my, available through Cisco.com at the following URL:

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

Benefits

The ATM SNMP Trap and OAM enhancements

•Enable you to use SNMP to detect the recovery of PVCs that have gone down.

•Enable you to use SNMP to detect when OAM loopback for a PVC has failed.

•Keep the PVC in the up state when OAM loopback has failed, allowing for the continued flow of data.

•Provide VPI/VCI information in the ATM PVC traps, letting you know which PVC has changed operational state or has had an OAM loopback failure.

•Provide statistics on the number of state transitions a PVC goes through.

Restrictions

Extended ATM PVC traps cannot be used at the same time as the legacy ATM PVC trap. The legacy ATM PVC trap must be disabled by using the no snmp-server enable traps atm pvc command before extended ATM PVC traps can be configured.

ATM PVC UP traps are not generated for newly created PVCs. They are generated only for PVCs that go from the down state to the up state.

Related Documents

For more information on configuring OAM and ATM PVC trap support, see the following documents:

•The "Configuring ATM" chapter of the Cisco IOS Wide-Area Networking Configuration Guide, Release 12.2.

•The "ATM Commands" chapter of the Cisco IOS Wide-Area Networking Command Reference, Release 12.2.

For information on configuring SNMP, see the following documents:

•The "Configuring SNMP Support" chapter of the Cisco IOS Configuration Fundamentals Configuration Guide, Release 12.2

•The "SNMP Commands" chapter of the Cisco IOS Configuration Fundamentals Command Reference, Release 12.2

Supported Platforms

•Cisco 2600 series

•Cisco 3660

•Cisco 7200 series

•Cisco 7500 series (Cisco IOS Release 12.2(4)T3 and later)

Platform Support Through Feature Navigator

Cisco IOS software is packaged in feature sets that support specific platforms. To get updated information regarding platform support for this feature, access Feature Navigator. Feature Navigator dynamically updates the list of supported platforms as new platform support is added for the feature.

Feature Navigator is a web-based tool that enables you to quickly determine which Cisco IOS software images support a specific set of features and which features are supported in a specific Cisco IOS image.

To access Feature Navigator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions at http://www.cisco.com/register.

Feature Navigator is updated when major Cisco IOS software releases and technology releases occur. As of May 2001, Feature Navigator supports M, T, E, S, and ST releases. You can access Feature Navigator at the following URL:

http://www.cisco.com/go/fn.

Supported Standards, MIBs, and RFCs

Standards

No new or modified standards are supported by this feature.

MIBs

This feature provides enhancements to the ATM PVC trap MIB. The MIB file CISCO-IETF-ATM2-PVCTRAP-MIB-EXTN.my can be downloaded from the Cisco MIB website on Cisco.com at

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

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

No new or modified RFCs are supported by this feature.

Prerequisites

Before you enable ATM PVC trap support, you must configure SNMP support and an IP routing protocol on your router. For more information about configuring SNMP support, refer to the chapter "Configuring SNMP Support" in the Cisco IOS Configuration Fundamentals Configuration Guide. For information about configuring IP routing protocols, refer to the section "IP Routing Protocols" in the Cisco IOS IP Configuration Guide.

To receive PVC failure notification and to allow access to PVC status tables on your router, you must have the Cisco extended ATM PVC trap MIB called CISCO-IETF-ATM2-PVCTRAP-MIB-EXTN.my compiled in your network management system (NMS) application. You can find this MIB on the Web at Cisco's MIB website that has the URL http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

The legacy ATM PVC trap must be disabled by using the no snmp-server enable traps atm pvc command before extended ATM PVC traps can be configured.

Configuration Tasks

See the following sections for configuration tasks for the ATM SNMP trap and OAM enhancements. Each task in the list is identified as either optional or required.

•Configuring Extended ATM PVC Trap Support (required)

•Enabling OAM Management (required)

•Verifying ATM PVC Traps (optional)

Configuring Extended ATM PVC Trap Support

To configure extended ATM PVC trap support, use the following command in global configuration mode:

Command
Purpose

Router(config)# snmp-server enable traps atm pvc extension {up | down | oam failure loopback}

Enables the sending of extended ATM PVC traps. The keywords are as follows:

•up—Enables ATM PVC up traps, which are generated when a PVC changes from the down to up state.

•down—Enables ATM PVC failure traps, which are generated when a PVC changes from the up to down state.

•oam failure loopback—Enables ATM PVC OAM failure traps, which are generated when OAM loopback fails.


Enabling OAM Management

When you configure PVC trap support, you must also enable OAM management on the PVC. To enable OAM management, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# interface atm slot/0[.subinterface-number {multipoint | point-to-point}]


or

Router(config)# interface atm slot/port-adapter/0[.subinterface-number {multipoint | point-to-point}]


or

Router(config)# interface atm number[.subinterface-number {multipoint | point-to-point}]

Specifies the ATM interface using the appropriate form of the interface atm command.1

Step 2 

Router(config-if)# pvc [name] vpi/vci

Enables the PVC.

Step 3 

Router(config-if-atm-vc)# oam-pvc manage

Enables end-to-end OAM management for an ATM PVC.

1 To determine the correct form of the interface atm command, consult your ATM network module, port adapter, or router documentation.

Verifying ATM PVC Traps

To verify the configuration of ATM PVC traps, use the show running-config command. To view the status of ATM VCs, use the show atm vc command.

Monitoring and Maintaining ATM PVC Traps

To monitor ATM PVC trap performance, use the following commands in EXEC mode:

Command
Purpose

Router# debug atm errors

Displays ATM errors.

Router# debug atm oam

Displays information about ATM OAM events.

Router# debug snmp packets

Displays information about every SNMP packet sent or received by the router.


Configuration Examples

This section provides the following configuration example:

•Configuring Extended ATM PVC Trap Support: Example

•Extended ATM PVC Traps Output: Examples

Configuring Extended ATM PVC Trap Support: Example

The following example shows all three of the extended ATM PVC traps enabled on a router. If PVC 0/1 leaves the up state, leaves the down state, or has an OAM loopback failure, host 172.16.61.90 will receive the SNMP notifications: 

! Configure SNMP support and an IP routing protocol on your router:

Router(config)# snmp-server community public ro

Router(config)# snmp-server host 172.16.61.90 public 

Router(config)# ip routing

Router(config)# router igrp 109

Router(config-router)# network 172.16.0.0

!

! Enable extended ATM PVC trap support and OAM management:

Router(config)# snmp-server enable traps atm pvc extension down

Router(config)# snmp-server enable traps atm pvc extension up

Router(config)# snmp-server enable traps atm pvc extension oam failure loopback

Router(config)# interface atm 1/0.1 

Router(config-if)# pvc 0/1

Router(config-if-atm-vc)# oam-pvc manage

Extended ATM PVC Traps Output: Examples

This section contains examples of output for the extended ATM PVC traps.

Extended ATM PVC Failure Trap Output: Example

The following example shows output for the extended ATM PVC failure trap for PVCs 1/100, 1/102, and 1/103. Note that only one trap is generated for all the PVCs associated with the same interface or subinterface (in contrast to the legacy ATM PVC failure trap, which generates a separate trap for each PVC). The VPI/VCI information and timing information is located in the objects associated with the trap. 

00:23:56:SNMP:Queuing packet to 1.1.1.1

00:23:56:SNMP:V2 Trap, reqid 2, errstat 0, erridx 0

sysUpTime.0 = 143636

snmpTrapOID.0 = atmIntfPvcFailuresTrap

ifEntry.1.19 = 19

atmIntfPvcFailures.2 = 7

atmIntfCurrentlyFailingPVcls.2 = 3

atmPVclLowerRangeValue.19.1.2 = 102

atmPVclHigherRangeValue.19.1.2 = 103

atmPVclRangeStatusChangeStart.19.1.2 = 140643

atmPVclRangeStatusChangeEnd.19.1.2 = 140698

atmPVclStatusTransition.19.1.100 = 1

atmPVclStatusChangeStart.19.1.100 = 140636

atmPVclStatusChangeEnd.19.1.100 = 140636

00:23:56:SNMP:Packet sent via UDP to 1.1.1.1

Extended ATM PVC Up Trap Output: Example

The following example shows output for the extended ATM PVC up trap for PVCs 1/100, 1/102, and 1/103: 

00:31:29:SNMP:Queuing packet to 1.1.1.1

00:31:29:SNMP:V2 Trap, reqid 2, errstat 0, erridx 0

sysUpTime.0 = 188990

snmpTrapOID.0 = atmIntfPvcUpTrap

ifEntry.1.19 = 19

atmIntfCurrentlyDownToUpPVcls.2 = 3

atmPVclLowerRangeValue.19.1.2 = 102

atmPVclHigherRangeValue.19.1.2 = 103

atmPVclRangeStatusChangeStart.19.1.2 = 186005

atmPVclRangeStatusChangeEnd.19.1.2 = 186053

atmPVclStatusTransition.19.1.100 = 1

atmPVclStatusChangeStart.19.1.100 = 185990

atmPVclStatusChangeEnd.19.1.100 = 185990

00:31:30:SNMP:Packet sent via UDP to 1.1.1.1

Command Reference

This section documents the new command that configures the ATM SNMP Trap and OAM Enhancements feature. All other commands used with this feature are documented in the Cisco IOS Release 12.2 command reference publications:

•snmp-server enable traps atm pvc extension

snmp-server enable traps atm pvc extension

To enable the sending of extended ATM permanent virtual circuit (PVC) Simple Network Management Protocol (SNMP) notifications, use the snmp-server enable traps atm pvc extension command in global configuration mode. To disable extended ATM PVC-specific SNMP notifications, use the no form of this command.

snmp-server enable traps atm pvc extension {up | down | oam failure loopback}

no snmp-server enable traps atm pvc extension {up | down | oam failure loopback}

Syntax Description

up

Enables extended ATM PVC up traps, which are generated when a PVC changes from the down to the up state.

down

Enables extended ATM PVC failure traps, which are generated when a PVC changes from the up to the down state.

oam failure loopback

Enables extended ATM PVC OAM failure traps, which are generated when OAM loopback fails.


Defaults

SNMP notifications are disabled by default.
The interval between succesive traps is 30 seconds.

Command Modes

Global configuration

Command History

Release
Modification

12.2(4)T

This command was introduced for those platforms that support ATM PVC Management.


Usage Guidelines

For PVCs that are not part of a range, extended ATM PVC traps include virtual path identifier/virtual channel indentifier (VPI/ VCI) information, the number of state transitions a PVC goes through in an interval, and the timestamp for the start and end of the transitions. For PVCs that are part of a range, extended ATM PVC traps include the first and last VPI/VCI of the range and the timestamp for the first failure and the last failure within the same range.

Extended ATM PVC traps cannot be used at the same time as the legacy ATM PVC trap. The legacy ATM PVC trap must be disabled by using the no snmp-server enable traps atm pvc command before extended ATM PVC traps can be configured.

The extended ATM PVC failure trap (which is is enabled by the snmp-server enable traps atm pvc extension down command) is the same trap as the legacy ATM PVC failure trap (which is enabled by the snmp-server enable traps atm pvc command), but with the the following differences:

•The extended ATM PVC failure trap contains information in the form of VPI/VCI ranges.

•The extended ATM PVC failure trap contains timestamps for when PVCs go down.

•The legacy ATM PVC failure trap contains only one VPI/VCI per trap.

When the ATM PVC OAM failure trap is enabled, the PVC remains in the up state when OAM loopback fails so that the flow of data will still be possible. If the ATM PVC OAM failure trap is not enabled, the PVC will be placed in the down state when OAM loopback fails.

OAM management must be enabled on the PVC by using the oam-pvc manage command before you can use ATM PVC traps.

SNMP notifications can be sent as traps or inform requests. This command enables both traps and inform requests for the specified notification types. ATM notifications are defined in the CISCO-IETF-ATM2-PVCTRAP-MIB.my file, available from the Cisco FTP site at ftp://www.cisco.com/public/mibs/v2/.

ATM PVC traps are generated at the end of the notification interval. It is possible to generate all three types of ATM PVC traps (the ATM PVC failure trap, ATM PVC up trap, and ATM PVC OAM failure trap) at the end of the same notification interval; however, only one type of trap will be generated for each PVC.

The snmp-server enable traps atm pvc command is used in conjunction with the snmp-server host command. Use the snmp-server host command to specify which host or hosts receive SNMP notifications. In order to send notifications, you must configure at least one snmp-server host command.

Examples

Configuring Extended ATM PVC Traps: Example

The following example shows all three of the extended ATM PVC traps enabled on a router. If PVC 0/1 leaves the up state, leaves the down state, or has an OAM loopback failure, host 172.16.61.90 will receive the SNMP notifications: 

! Configure SNMP support and an IP routing protocol on your router:

Router(config)# snmp-server community public ro

Router(config)# snmp-server host 172.16.61.90 public 

Router(config)# ip routing

Router(config)# router igrp 109

Router(config-router)# network 172.16.0.0

!

! Enable extended ATM PVC trap support and OAM management:

Router(config)# snmp-server enable traps atm pvc extension down

Router(config)# snmp-server enable traps atm pvc extension up

Router(config)# snmp-server enable traps atm pvc extension oam failure loopback

Router(config)# interface atm 1/0.1 

Router(config-if)# pvc 0/1

Router(config-if-atm-vc)# oam-pvc manage

Extended ATM PVC Failure Trap Output: Example

The following example shows output for extended ATM PVC failure trap for PVCs 1/100, 1/102, and 1/103. Note that only one trap is generated for all the PVCs associated with the same interface or subinterface (in contrast to the legacy ATM PVC failure trap, which generates a separate trap for each PVC). The VPI/VCI information and timing information are located in the objects associated with the trap. 

00:23:56:SNMP:Queuing packet to 1.1.1.1

00:23:56:SNMP:V2 Trap, reqid 2, errstat 0, erridx 0

sysUpTime.0 = 143636

snmpTrapOID.0 = atmIntfPvcFailuresTrap

ifEntry.1.19 = 19

atmIntfPvcFailures.2 = 7

atmIntfCurrentlyFailingPVcls.2 = 3

atmPVclLowerRangeValue.19.1.2 = 102

atmPVclHigherRangeValue.19.1.2 = 103

atmPVclRangeStatusChangeStart.19.1.2 = 140643

atmPVclRangeStatusChangeEnd.19.1.2 = 140698

atmPVclStatusTransition.19.1.100 = 1

atmPVclStatusChangeStart.19.1.100 = 140636

atmPVclStatusChangeEnd.19.1.100 = 140636

00:23:56:SNMP:Packet sent via UDP to 1.1.1.1

Extended ATM PVC Up Trap Output: Example

The following example shows output for the extended ATM PVC up trap for PVCs 1/100, 1/102, and 1/103: 

00:31:29:SNMP:Queuing packet to 1.1.1.1

00:31:29:SNMP:V2 Trap, reqid 2, errstat 0, erridx 0

sysUpTime.0 = 188990

snmpTrapOID.0 = atmIntfPvcUpTrap

ifEntry.1.19 = 19

atmIntfCurrentlyDownToUpPVcls.2 = 3

atmPVclLowerRangeValue.19.1.2 = 102

atmPVclHigherRangeValue.19.1.2 = 103

atmPVclRangeStatusChangeStart.19.1.2 = 186005

atmPVclRangeStatusChangeEnd.19.1.2 = 186053

atmPVclStatusTransition.19.1.100 = 1

atmPVclStatusChangeStart.19.1.100 = 185990

atmPVclStatusChangeEnd.19.1.100 = 185990

00:31:30:SNMP:Packet sent via UDP to 1.1.1.1

Related Commands

Command
Description

oam-pvc manage

Enables end-to-end F5 OAM loopback cell generation and OAM management for an ATM PVC or VC class.

show atm pvc

Displays all ATM PVCs and traffic information.

snmp-server enable traps

Enables all available SNMP notifications on your system.

snmp-server enable traps atm pvc

Enables the sending of legacy ATM PVC DOWN traps.

snmp-server host

Specifies the recipient of an SNMP notification operation.

snmp-server trap-source

Specifies the interface from which an SNMP trap should originate.


Glossary

inform—SNMP trap message that includes a delivery confirmation request.

MIB—Management Information Base. Database of network management information that is used and maintained by a network management protocol such as SNMP. The value of a MIB object can be changed or retrieved using SNMP commands, usually through a network management system (NMS). MIB objects are organized in a tree structure that includes public (standard) and private (proprietary) branches.

NMS—network management system. An application or suite of applications designed to monitor networks using SNMP. CiscoView is one example of an NMS.

OAM—Operation, Administration, and Maintenance. ATM Forum specifies OAM cells used to monitor virtual circuits. OAM cells provide a virtual circuit-level loopback in which a router responds to the cells, demonstrating that the circuit is up and the router is operational.

PVC—permanent virtual circuit. Virtual circuit that is permanently established. PVCs save bandwidth associated with circuit establishment and teardown in situations where certain virtual circuits must exist all the time. In ATM terminology, PVC also stands for permanent virtual connection.

SNMP—Simple Network Management Protocol. An application-layer protocol that provides a message format for communication between SNMP managers and agents and is used almost exclusively in TCP/IP networks. SNMP provides a means to monitor and control network devices and to manage configurations, statistics collection, performance, and security.

trap—A message from an SNMP agent alerting the SNMP manager to a condition on the network.

VCI—virtual channel identifier. 16-bit field in the header of an ATM cell. The VCI, together with the VPI, is used to identify the next destination of a cell as it passes through a series of ATM switches on its way to its destination. ATM switches use the VPI/VCI fields to identify the next network VCL that a cell needs to transit on its way to its final destination.

VCL—virtual channel link. Connection between two ATM devices.

VPI—virtual path identifier. eight-bit field in the header of an ATM cell. The VPI, together with the VCI, is used to identify the next destination of a cell as it passes through a series of ATM switches on its way to its destination. ATM switches use the VPI/VCI fields to identify the next VCL that a cell needs to transit on its way to its final destination. The function of the VPI is similar to that of the DLCI in Frame Relay.