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Cisco ONS 15310-MA SDH Troubleshooting Guide, Release 9.0
78-18663-01
Chapter 2 Alarm Troubleshooting
Alarm Procedures
2.7.130 AU-LOP
Default Severity: Critical (CR), Service-Affecting (SA)
SDH Logical Objects: VCMON-HP, VCTRM-HP
A Loss of Pointer Path alarm indicates that the SDH path pointer in the overhead has been lost. LOP
occurs when valid H1/H2 pointer bytes are missing from the overhead. Receiving equipment monitors
the H1/H2 pointer bytes to locate the SDH payload. An AU-LOP alarm occurs when eight, nine, or ten
consecutive frames do not have valid pointer values. The alarm clears when three consecutive valid
pointers are received.
The AU-LOP alarm can occur when the received payload does not match the provisioned payload. The
alarm is caused by a circuit type mismatch on the concatenation facility. For example, if an VC3 is sent
across a circuit provisioned for VC4, an AU-LOP alarm occurs.
Clear the AU-LOP Alarm
Step 1 In node view, click the Circuits tab and view the alarmed circuit.
Step 2 Verify the circuit size listed in the Size column. If the size is different from what is expected, such as an
VC4 instead of an VC3, this raises the alarm.
Step 3 If you have been monitoring the circuit with optical test equipment, a mismatch between the provisioned
circuit size and the size expected by the test set can cause this alarm. Ensure that the test set monitoring
is set up for the same size as the circuit provisioning.
For instructions to use the optical test set, consult the manufacturer.
Caution Always use the supplied electrostatic discharge wristband when working with a powered
ONS 15310-MA SDH.
Step 4 If the error is not due to an incorrectly configured test set, the error is in the provisioned CTC circuit
size. Complete the “Delete a Circuit” procedure on page 2-154.
Step 5 Recreate the circuit for the correct size. For procedures, refer to the “Create Circuits” chapter in the
Cisco ONS15310-MA SDH Procedure Guide.
Step 6 If the alarm does not clear, log into the Technical Support Website at
http://www.cisco.com/cisco/web/support/index.html for more information or call Cisco TAC
(1-800-553-2447) in order to report a Service-Affecting (SA) problem.
2.7.131 TU-LOP
Default Severity: Major (MJ), Service-Affecting (SA)
SDH Logical Objects: VCMON-LP, VCTRM-LP
The LOP VT alarm indicates a loss of pointer at the VT/VC level. This alarm can occur when the
received payload does not match the provisioned payload. TU-LOP is caused by a circuit size mismatch
on the concatenation facility.