Cisco Unified IP Phone Resets Unexpectedly
Static IP Address Settings Errors
Problem
The static IP address assigned to the phone may be incorrect.
Solution
If the phone is assigned a static IP address, verify that you have entered the correct settings. See
Menus, on page 35
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 the same switch as the 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. See the
Unified SIP Phone 3905 and VLAN Interaction, on page 22
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 Applications on the phone and choosing Admin Settings > Status > Network
Statistics. If the phone was recently reset, one of these messages appears:
• If the Restart Cause field displays Reset-Reset, the phone closed due to receiving a Reset/Reset from
Cisco Unified Communications Manager Administration.
• If the Restart Cause field displays Reset-Restart, the phone closed due to receiving a Reset/Restart from
Cisco Unified Communications Manager Administration.
DNS or Other Connectivity Errors
Problem
The phone reset continues and you suspect DNS or other connectivity issues.
Cisco Unified SIP Phone 3905 Administration Guide for Cisco Unified Communications Manager 8.6 (SIP)
84
for more information.
Troubleshooting and Maintenance
for details.
Configuration
Cisco