Cisco Systems OL-21035-01 manual Where to Go for More Troubleshooting Information

Table 6-2

ATA 187 Troubleshooting (continued)

Summary

Explanation

Loopback condition

A loopback condition can occur when the following conditions are

met:

• The SW Port Configuration option in the Network

Configuration menu on the phone is set to 10 Half

(10-BaseT/half duplex)

• The phone receives power from an external power supply

• The phone is powered down (the power supply is disconnected)

In this case, the switch port on the phone can become disabled and

the following message will appear in the switch console log:

HALF_DUX_COLLISION_EXCEED_THRESHOLD

To resolve this problem, re-enable the port from the switch.

One-way audio

When at least one person in a call does not receive audio, IP

connectivity between phones is not established. Check the

configurations in routers and switches to ensure that IP connectivity

is properly configures.

Peer to peer image distribution

If the peer to peer image distribution fails, the phone will default to

fails.

using the TFTP server to download firmware. Access the log

messages stored on the remote logging machine to help debug the

peer to peer image distribution feature.

Note These log messages are different than the log messages sent

to the phone log.

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.

OL-21035-01

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