Verifying Dhcp Settings; Checking Static Ip Address Settings; Verifying The Voice Vlan Configuration; Verifying That The Phones Have Not Been Intentionally Reset - Cisco CP-7961G Administration Manual

Chapter 9 Troubleshooting and Maintenance

Verifying DHCP Settings

The following suggestions can help you determine if the phone has been properly configured to use
DHCP:
1.
2.
3.
Cisco Unified IP Phones 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 phone to
restart and request a new IP address from the DHCP server.

Checking Static IP Address Settings

If the phone has been assigned a static IP address, verify that you have entered the correct settings. See
Network Configuration Menu, page 4-5

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
Understanding How the Cisco Unified IP Phone Interacts with the VLAN, page 2-2

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 Settings button on the phone and choosing Status >
Network Statistics. If the phone was recently reset one of these messages appears:
•
•

Eliminating DNS or Other Connectivity Errors

If the phone continues to reset, follow these steps to eliminate DNS or other connectivity errors:
OL-21011-01
Verify that you have properly configured the phone to use DHCP. See
page 4-5 for more information.
Verify that the DHCP server has been set up properly.
Verify the DHCP lease duration. Cisco recommends that you set it to 8 days.
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.
Cisco Unified IP Phone Administration Guide for Cisco Unified Communications Manager 8.0 (SCCP and SIP)
Cisco Unified IP Phone Resets Unexpectedly
for more information.
Network Configuration Menu,
for details.
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