On the 7750 SR, the ATM ping OAM loopback feature can be enabled on an ATM SAP for a period of time configured through the interval and the send-count parameters. When the ATM SAP terminates on IES or VPRN services, a failure of the loopback state machine does not bring down the Layer 3 interface. Only receiving AIS/RDI OAM cells or entering the AIS/RDI state brings down the Layer 3 interface.
The ATM ping OAM loopback feature can also be enabled on a continuous basis on an ATM SAP terminating on IES or VPRN services. When the loopback state machine fails, the Layer 3 interface is brought down.
The ATM OAM loopback parameters must first be enabled and configured in the config>system>atm>oam context, and then enabled in the IES or VPRN service interface SAP atm oam context.
See the 7450 ESS, 7750 SR, 7950 XRS, and VSR Layer 3 Services Guide: IES and VPRN for further information. For command descriptions, see the 7450 ESS, 7750 SR, 7950 XRS, and VSR Classic CLI Command Reference Guide.