3
Verify the DHCP lease duration. Cisco recommends that you set it to 8 days.
Cisco Unified IP Phone 7971G-GE and 7970G send messages with request type 151 to renew their DHCP
address leases. If the DHCP server expects messages with request type 150, the lease will be denied,
forcing the Cisco Unified IP Phone 7971G-GE and 7970G to restart and request a new IP address from
the DHCP server.
Static IP Address Setting Errors
Problem
The static IP address assigned to the phone may be incorrect.
Solution
If the phone has been assigned a static IP address, verify that you have entered the correct settings.
Voice VLAN Setup Errors
Problem
If the Cisco Unified IP Phone appears to reset during heavy network usage (for example, following extensive
web surfing on a computer connected to same switch as phone), it is likely that you do not have a voice VLAN
configured.
Solution
Isolating the phones on a separate auxiliary VLAN increases the quality of the voice traffic.
Phones Have Not Been Intentionally Reset
Problem
If you are not the only administrator with access to Cisco Unified Communications Manager, you should
verify that no one else has intentionally reset the phones.
Solution
You can check whether a Cisco Unified IP Phone received a command from Cisco Unified Communications
Manager to reset by pressing the
Applications Menu
button on the phone and choosing
Settings
>
Status
>
Network Statistics
. If the phone was recently reset one of these messages appears:
•
Reset-Reset: Phone received a Reset-Reset request from Cisco Unified Communications Manager
Administration.
•
Reset-Restart: Phone received a Reset-Restart request from Cisco Unified Communications Manager
Administration.
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