Cisco 7975G - Page 182

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Cisco Unified IP Phone 7975G Administration Guide for Cisco Unified Communications Manager 6.0
OL-12642-01
Chapter 9 Troubleshooting and Maintenance
General Troubleshooting Tips
Phone call cannot be
established
The phone does not have a DHCP IP address, is
unable to register to Cisco Unified Communications
Manager, and shows a Configuring IP or Registering
message.
Verify the following:
1. The Ethernet cable is attached.
2. The Cisco CallManager service is running on
the Cisco Unified Communications Manager
server.
3. Both phones are registered to the same Cisco
Unified Communications Manager.
4. Audio server debug and capture logs are enabled
for both phones. If needed, enable Java debug.
Call established with the
iLBC protocol does not
show that the iLBC
codec is being used
Call statistics display does not show iLBC as the
receiver/sender codec.
1. Check the following using the Cisco Unified
Communications Manager administration
pages:
– Both phones are in the iLBC device pool.
– The iLBC device pool is configured with
the iLBC region.
– The iLBC region is configured with the
iLBC codec.
2. Capture a sniffer trace between the phone and
Cisco Unified Communications Manager and
verify that SCCP messages,
OpenReceiveChannel, and
StationMediaTransmit messages have media
payload type value equal to 86. If so, the
problem is with the phone; otherwise the
problem is with the Cisco Unified
Communications Manager configuration.
3. Enable audio server debug and capture logs
from both phones. If needed, enable Java debug.
Table 9-2 Cisco Unified IP Phone Troubleshooting (continued)
Summary Explanation