Troubleshooting guide

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Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
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Chapter 6 Troubleshooting the Cisco PGW 2200 Softswitch Platform
Resolving Bearer Channel Connection Problems
Note You can configure the Cisco PGW 2200 Softswitch software to issue individual or group supervision
messages for point codes that are associated with an ISUP signaling service. ISUP signaling services
issue group supervision messages by default. If you configure an ISUP signaling service to issue
individual supervision messages, specifying the range option causes the system to issue individual
supervision messages for each CIC in the range, instead of a single group supervision message.
For example, to reset CICs number 1 through 20, which are associated with a signaling service called
ss7svc1, enter the
reset-cic:ss7svc1:cic=1,rng=19 command:
To verify that the CICs are successfully reset, retrieve the status of the affected CICs as described in the
“Verifying CIC States” section on page 3-15. If the CICs are still blocked, see the “Resolving Stuck
CICs” section on page 6-141.
Resolving Stuck CICs
A CIC is stuck or hung when one or more bearer channels that are associated with a single call instance
refuse to return to the idle call state, despite attempts to manually clearit by issuing the reset-cic MML
command. Usually, a CIC is stuck when transient network glitches or configuration errors trigger
protocol state machine errors. Typically these conditions result in a mismatch between the call state of
a CIC on the Cisco PGW 2200 Softswitch and the call state for the associated span and bearer channel
(also known as time slot) on the media gateway.
The Cisco PGW 2200 Softswitch can automatically detect and terminate stuck CICs. The system runs
an audit cron job once a day that verifies, using the sta-aud MML command, that the call states for the
CICs on the Cisco PGW 2200 Softswitch match the associated states for the spans and bearer channels
on the media gateway. If the audit finds that the Cisco PGW 2200 Softswitch call states on a CIC show
that a call is in progress while the associated media gateway span and bearer channel states are idle, the
system attempts to release the identified CIC by issuing the stp-call MML command. The stp-call MML
command monitors for the release of the CIC. If the CIC is not released within 1 to 2 minutes, the system
forcefully releases the CIC. When a CIC is forcefully released, a minimal CDR is written, with a cause
of Temporary Failure.
Note If you believe CICs are stuck CICs, and do not want to wait for the periodic audit cron job to run, or if
the audit cron job seems unable to clear the CICs, perform the steps that are identified in the “Manually
Resolving Stuck CICs” section on page 6-142.
Note The format of the CDR depends upon your configuration of the associated XECfgParm.dat parameters.
For more information on XECfgParm.dat configuration, see
Cisco PGW 2200 Softswitch Release 9 Software Installation and Configuration Guide. For more
information on CDRs, see Cisco PGW 2200 Softswitch Release 9 Billing Interface Guide.
To run the audit cron job more than once a day, increase the frequency of the audit in the mgcusr crontab
entry. You must have system administration authority to use crontab. For more information on crontab,
enter the UNIX man crontab command on the Cisco PGW 2200 Softswitch.