Cisco 8831NR Administration Manual page 134

Cisco Unified IP Conference Phone Cannot Obtain IP Address
Solution
A conference phone can register with a Cisco Unified Communications Manager server only if the conference
phone has been added to the server or if autoregistration is enabled. Review the information and procedures
in the
section to ensure that the conference phone has been added to Cisco Unified Communications Manager.
To verify that the conference phone is in the Cisco Unified Communications Manager database, choose
Device > Phone from Cisco Unified Communications Manager Administration and search for the conference
phone based on its MAC Address. For information about determining a MAC address, see the
Phone MAC Address Determination, on page 42
If the conference phone is already in the Cisco Unified Communications Manager database, its configuration
file may be damaged. See the
Cisco Unified IP Conference 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 conference phone is connected 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 Unified IP Conference Phone Resets Unexpectedly
If users report that their phones are resetting during calls or while idle on their desk, you should investigate
the cause. If the network connection and Cisco Unified Communications Manager connection are stable, a
phone should not reset on its own.
Typically, a phone resets if it has problems connecting to the Ethernet network or to Cisco Unified
Communications Manager. The following sections can help you identify the cause of a conference phone
resetting in your network.
Physical Connection Problems
Problem
The physical connection to the LAN may be broken.
Solution
Verify that the Ethernet connection to which the phone is connected is up. For example, check if the particular
port or switch to which the phone is connected is down and that the switch is not rebooting. Also make sure
that there are no cable breaks.
Cisco Unified IP Conference Phone 8831 and 8831NR Administration Guide
124
Cisco Unified Communications Manager Administration Conference Station Addition, on page 41
Configuration File Corruption, on page 123
section.
section for assistance.
Troubleshooting and Maintenance
Conference