Filter
Top Products
12-7
Cisco Unified IP Phone 8961, 9951, and 9971 Administration Guide for Cisco Unified Communications Manager 8.5 (SIP)
OL-20861-01
Chapter 12 Troubleshooting and Maintenance
Cisco Unified IP Phone Resets Unexpectedly
Verifying DHCP Settings
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. See the “Ethernet Setup Menu”
section on page 7-4 for more information.
2. Verify that the DHCP server has been set up properly.
3. Verify the DHCP lease duration. Cisco recommends that you set it to 8 days.
Checking Static IP Address Settings
If the phone has been assigned a static IP address, verify that you have entered the correct settings. See
the “Ethernet Setup Menu” section on page 7-4 for more information.
Verifying the Voice VLAN Configuration
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.
Isolating the phones on a separate auxiliary VLAN increases the quality of the voice traffic. See the
“Understanding How the Cisco Unified IP Phone Interacts with the VLAN” section on page 2-2 for
details.
Verifying that the Phones Have Not Been Intentionally Reset
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.
You can check whether a Cisco Unified IP Phone received a command from Cisco Unified
Communications Manager to reset by pressing the Applications button on the phone and choosing
Administrator Settings > Status > Network Statistics. If the phone was recently reset, one of these
messages appears:
• Reset-Reset—Phone closed due to receiving a Reset/Reset from Cisco Unified Communications
Manager Administration.
• Reset-Restart—Phone closed due to receiving a Reset/Restart from Cisco Unified Communications
Manager Administration.