Cisco Systems 6921 Checking Static IP Address Settings, Verifying the Voice Vlan Configuration

Chapter

Cisco Unified IP Phone Resets Unexpectedly

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 “Network Setup Menu” section on page 4-4for 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 2-2for 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.

Eliminating DNS or Other Connectivity Errors

If the phone continues to reset, follow these steps to eliminate DNS or other connectivity errors:

Procedure

Step 1 Use the Reset Settings menu to reset phone settings to their default values. See the “Resetting or Restoring the Cisco Unified IP Phone” section on page 9-12for details.

Step 2 Modify DHCP and IP settings:

a.Disable DHCP. See the “Network Setup Menu” section on page 4-4for instructions.

b.Assign static IP values to the phone. See the “Network Setup Menu” section on page 4-4for instructions. Use the same default router setting used for other functioning Cisco Unified IP Phones.

c.Assign a TFTP server. See the “Network Setup Menu” section on page 4-4for instructions. Use the same TFTP server used for other functioning Cisco Unified IP Phones.

Step 3 On the Cisco Unified Communications Manager server, verify that the local host files have the correct Cisco Unified Communications Manager server name mapped to the correct IP address.

Cisco Unified IP Phone 6921, 6941, 6945, and 6961 Administration Guide for Cisco Unified Communications Manager 8.5 (SCCP and SIP)

OL-23769-01 9-7