Configuring ATM PVC F5 OAM Recovery Traps

F5 OAM cells are used to detect connectivity failures and recoveries at the ATM layer. Before the introduction of this feature, Cisco IOS software provided support for SNMP traps (also called SNMP notifications) for F5 end-to-end loopback, and F5 AIS/RDI connectivity failures on a PVC. The ATM PVC F5 OAM Recovery Traps feature introduces SNMP traps that notify the network management system (NMS) when connectivity is restored to a PVC after the following types of failures:

• F5 OAM end-to-end loopback failures
• F5 OAM segment AIS/RDI failures
• F5 OAM end-to-end AIS/RDI failures

Information in the traps includes the number of PVCs that recovered and time stamps indicating when the first and last recoveries occurred during the notification interval.

To limit the amount of traffic that can be generated by the F5 OAM failure and recovery traps, only one trap of each type can be generated in each trap interval. Each trap can report on multiple PVCs, and successive PVCs that have the same failure or recovery are reported as a range.

In addition to the traps, MIB tables are maintained to provide information about the failures and recoveries on PVCs.

For a complete description of the extended ATM PVC TRAP MIB, including the supported notifications and tables, see the MIB file called CISCO-ATM-PVCTRAP-EXTN-MIB.my, available through Cisco.com at the following URL:

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

Before the introduction of this feature, when F5 OAM failures were detected on PVCs, failure notifications were sent to the NMS, and the operational state of the PVC was kept up. There was no mechanism for notifying the NMS when connectivity was restored to the PVCs after F5 OAM failures. The F5 OAM Recovery Traps feature introduces traps that asynchronously notify the NMS when PVCs have recovered from F5 OAM failures.

ATM PVC trap support provides ATM PVC failure notification by sending a trap when a PVC on an ATM interface fails or leaves the UP operational state. F5 OAM cells are used to detect connectivity failures and recoveries at the ATM layer. The operator informs the NMS of these OAM failures using ATM PVC traps. The following ATM PVC Traps are supported:

• ATM PVC DOWN TRAP
• ATM PVC F5 Loop back failure TRAP
• ATM PVC F5 Segment CC failure TRAP
• ATM PVC F5 End-to-End CC failure TRAP
• ATM PVC F5 AIS/RDI failure TRAP

When connectivity is restored, the PVC state is brought UP for allowing data transfer to take place over the PVC. This connectivity restoration uses the OAM cells. The following recovery traps are used to inform the NMS about the restoration of connectivity:

• ATM PVC UP TRAP
• ATM PVC F5 Loop back recovery TRAP
• ATM PVC F5 Segment CC recovery TRAP
• ATM PVC F5 End-to-End CC recovery TRAP
• ATM PVC F5 AIS/RDI recovery TRAP

To limit the amount of traffic that can be generated by the F5 OAM failure and recovery traps, only one trap of each type can be generated in each trap interval. Each trap can report on multiple PVCs, and successive PVCs that have the same failure or recovery are reported as a range.

The ATM PVC Trap Enhancements for Segment and End AIS/RDI failures feature addresses the issue of generating the separate ATM F5 segment and end AIS/RDI failure and recovery traps.

The ATM PVC TRAP Enhancement for Segment and End AIS/RDI Failures feature adds segment and end AIS/RDI Failure notification (traps) to the existing ATM PVC trap infrastructure. This feature adds the ifDescr object to the existing traps. The addition of this object allows the operator to get the interface name directly from the trap. The segment and end AIS/RDI failure and recovery traps are generated when AIS/RDI failure traps are enabled.

1.    enable

2.    configure terminal

3.    interface atm number

4.    ip address ip-address mask

5.    pvc [name ] vpi/vci

6.    oam-pvc manage [keep-vc-up [end aisrdi failure | seg aisrdi failure]]

7.    end

1.    enable

2.    configure terminal

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

4.    end

• Troubleshooting Tips

The following example shows how to enable ATM PVC OAM management:

Router(config)# interface ATM 2/0.1 point-to-point
 
Router(config-subif)# pvc pvc 45/54
	
Router(config-if-atm-vc)# oam-pvc manage
Router(config-if-atm-vc)# end

Note	Enhanced Interior Gateway Routing Protocol (EIGRP) must be configured on the router if you want the notification packets to be sent to the NMS.