Configuration File Corruption; Cisco Unified Communications Manager Phone Registration; Cisco Ip Phone Cannot Obtain Ip Address; Cisco Ip Phone Reset Problems - Cisco 7821 Administration Manual

Cisco IP Phone Reset Problems

Configuration File Corruption

Problem
If you continue to have problems with a particular phone that other suggestions in this chapter do not resolve,
the configuration file may be corrupted.
Solution
Create a new phone configuration file. See

Cisco Unified Communications Manager Phone Registration

Problem
The phone is not registered with the Cisco Unified Communications Manager
Solution
A Cisco IP Phone can register with a Cisco Unified Communications Manager server only if the phone is
added to the server or if autoregistration is enabled. Review the information and procedures in
Methods, on page 50
database.
To verify that the phone is in the Cisco Unified Communications Manager database, choose Device > Phone
from Cisco Unified Communications Manager Administration. Click Find to search for the phone based on
the MAC Address. For information about determining a MAC address, see
on page
If the phone is already in the Cisco Unified Communications Manager database, the configuration file may
be damaged. See

Cisco IP Phone Cannot Obtain IP Address

Problem
If a phone cannot obtain an IP address when it starts up, the phone may not be on the same network or VLAN
as the DHCP server, or the switch port to which the phone connects may be disabled.
Solution
Ensure that the network or VLAN to which the phone connects has access to the DHCP server, and ensure
that the switch port is enabled.
Cisco IP Phone Reset Problems
If users report that their phones are resetting during calls or while the phones are idle on their desk, you should
investigate the cause. If the network connection and Cisco Unified Communications Manager connection are
stable, a Cisco IP Phone should not reset.
Cisco IP Phone 7821, 7841, and 7861 Administration Guide for Cisco Unified Communications Manager 10.0
(SIP)
180
to ensure that the phone is added to the Cisco Unified Communications Manager
45.
Configuration File Corruption, on page 180
Create New Phone Configuration File, on page 191
for assistance.
for details.
Phone Addition
Determine Phone MAC Address,