Troubleshooting guide

BSR Troubleshooting Guide
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3. Check for signal degradation.
4. Check fiber optic connectors are broken or unclean.
5. Check the fiber cabling for damage or improper use. For example, SONET cables
may be turned beyond their bending radius.
LOP Determination
The SONET port may not be operational because there is a Loss of Pointer (LOP)
condition that occurs when there is the absence of valid H1/H2 pointer bytes for eight,
nine, or ten consecutive frames.
When a LOP condition occurs on a POS module, follow these steps to isolate the
condition:
1. Locate the SONET termination equipment.
2. To display information about a POS module port failure, use the show
controllers pos command in Privileged EXEC mode, as shown in the following
example:
BSR64000#show controllers pos <slot>/<port>
where:
slot is the POS module slot on the BSR 64000
port is the POS interface.
3. View the Active Alarm field in the show controllers pos command output to
determine if there is a LOP failure.
4. If LEDs on the POS module are green but you suspect that the module has
transmission problems on a port (causing a LOP on the other SONET device’s
receive port), check if a L-AIS or L-RDI failure has occurred. To do so, view the
Active Defect field in the show controllers pos command output. An L-AIS and
L-RDI failure is generated by the other SONET device and sent out its transmit
port when a failure is detected on its receive port. An L-RDI can indicate a LOP
failure condition.
5. If there is no L-AIS or L-RDI alarm, the problem may be with the other SONET
device.