Cisco Unified IP Phone Resets Unexpectedly
If users report that their phones are resetting during calls or while idle on their desk, you should investigate
the cause. If the network connection and Cisco Unified Communications Manager connection are stable, a
Cisco Unified IP Phone should not reset on its own.
Typically, a phone resets if it has problems connecting to the Ethernet network or to
Cisco Unified Communications Manager. These sections can help you identify the cause of a phone resetting
in your network:
Physical Connection Problems
Problem
The physical connection to the LAN may be broken.
Solution
Verify that the Ethernet connection to which the Cisco Unified IP Phone connects is up. For example, check
whether the particular port or switch to which the phone connects is down and that the switch is not rebooting.
Also ensure that no cable breaks exist.
Intermittent Network Outages
Problem
Your network may be experiencing intermittent outages.
Solution
Intermittent network outages affect data and voice traffic differently. Your network might be experiencing
intermittent outages without detection. If so, data traffic can resend lost packets and verify that packets are
received and transmitted. However, voice traffic cannot recapture lost packets. Rather than retransmitting a
lost network connection, the phone resets and attempts to reconnect to the network. Contact the system
administrator for information on known problems in the voice network.
DHCP Setting Errors
Problem
The DHCP settings may be incorrect.
Solution
The following suggestions can help you determine if the phone has been properly configured to use DHCP:
1
Verify that you have properly configured the phone to use DHCP. For more information, see
Network
Configuration Menu, on page 66
.
2
Verify that the DHCP server has been set up properly.
Cisco Unified IP Phone 7975G, 7971G-GE, 7970G, 7965G, and 7945G Administration Guide for Cisco Unified
Communications Manager 9.0 (SCCP and SIP)
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Troubleshooting and Maintenance
Cisco Unified IP Phone Resets Unexpectedly