Cisco VG30D, User Manual

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Cisco VG30D Voice Gateway User Guide
OL-19276-01
Chapter 10 Fault Determination
Diagnostic Procedures
Call Failures
Symptom
The STATUS LEDs show no faults, but no calls can be made. No indication of failure comes from
attached equipment.
Diagnostic Action
If the attached equipment is indicating a problem, you may be able to diagnose the fault by referring to
that equipment’s troubleshooting documentation.
Log in to the Cisco VG30D Voice Gateway by using a web browser. Check that the Diagnostic Overview
window shows no problems.
You can also monitor the Cisco VG30D Voice Gateway's ports in turn by using a Primary Rate signalling
protocol analyser. Check that calls are being received into the equipment and are being passed on to the
associated port. If not, and the cause is not obvious from inspection of the analyser diagnostics, contact
your support organisation for further guidance.
Symptom
Calls get dropped unexpectedly while in progress.
Diagnostic Action:
The commonest cause is transient transmission problems on the network-side connections. Check
whether errors are occurring on either port. Alternatively, request that the network provider run checks
on the connection.
Symptom
Higher than expected levels of unsuccessful call attempts.
Diagnostic Action:
In a DPNSS environment some or all channels may be incorrectly configured at Layer 3 (set to X or to
Y at both ends), which causes failure to resolve channel contention correctly. Therefore, the
configuration must be reviewed.
Symptom
DPNSS transparency is not achieved across a Q.931 network.
Diagnostic Action
The switching elements in Q.931 network do not support the Generic Functional Protocol, or do not have
this function enabled. Therefore, the configuration must be reviewed.
Symptom
DPNSS services requiring virtual calls do not work.
Diagnostic Action
Switching elements in the Q.931 network do not support non-call-associated signalling or do not have
this function enabled. Therefore, the configuration must be reviewed.