Troubleshooting guide

Troubleshooting SONET
9-127
Introduction
This chapter describes how to troubleshoot the Packet Over SONET (POS) access
module. When SONET network problems occur, the major failure conditions and
their associated alarm indicators occur.
The next sections describe how to respond to the following:
• Resolving Fault LED Issues
• Failed POS Module
• Handling Data Loss on SONET Link
Resolving Fault LED Issues
If the SONET port fault LED on the POS module is red, the port is not operational
and a loss of signal (LOS), loss of frame (LOF), and or loss of pointer (LOP)
condition exists.
LOS Determination
When a LOS condition occurs, follow these steps to resolve the LOS condition on a
POS module port:
1. Locate the SONET termination equipment.
2. To view the status of the SONET link, use the show controllers pos command in
Privileged EXEC mode, as shown in the following example:
BSR64000#show controllers pos <slot/port>
If the SONET link is down, the message
pos <slot>/<port> is down
appears.
3. View the Active Alarm field in the show controllers pos command output to
determine if there is an LOS failure on the POS module port.