Registering The Phone With Cisco Unified Communications Manager; Symptom: Cisco Unified Ip Phone Unable To Obtain Ip Address; Symptom: The Cisco Unified Ip Phone Displays Flashing Red Light - Cisco 6901 Administration Manual

Chapter 7 Troubleshooting and Maintenance
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Registering the Phone with Cisco Unified Communications Manager

A Cisco Unified IP Phone can register with a Cisco Unified Communications Manager server only if the
phone has been added to the server or (if autoregistration is enabled) there is a sufficient number of unit
licenses. Review the information and procedures in the
Communications Manager Database" section on page 2-7
Cisco Unified Communications Manager database.
To verify that the phone is in the Cisco Unified Communications Manager database, choose Device >
Phone > Find from Cisco Unified Communications Manager Administration to search for the phone
based on its MAC Address. For information about determining a MAC address, see the
Unified IP Phones with Different Protocols" section on page
If the phone is already in the Cisco Unified Communications Manager database, its configuration file
may be damaged. See the
For more information on licensing go to the
Communications Manager System Guide.

Symptom: Cisco Unified IP Phone Unable to Obtain IP Address

If a phone is unable to 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 is connected may be disabled. Make
sure that the network or VLAN to which the phone is connected has access to the DHCP server, and make
sure that the switch port is enabled.

Symptom: The Cisco Unified IP Phone Displays Flashing Red Light

When a Cisco Unified IP Phone boots, it performs an internal Power On Self Test (POST). POST checks
for existing encryption functionality. If POST detects that encryption functionality is missing, the phone
fails to boot, and the message indicator prompts the phone to display flashing red light.
To correct the problem, perform the following steps:
1.
2.
If the phone still does not start up properly, perform a factory reset of the phone. For instructions, see
Performing a Factory Reset, page
Cisco Unified IP Phone 6901 and 6911 Administration Guide for Cisco Unified Communications Manager 8.6 (SCCP and SIP)
OL-24582-01
Changing the buttons on a phone button template, or assigning a different phone button template to
a phone, may result in directory numbers that are no longer accessible from the phone. The directory
numbers are still assigned to the phone in the Cisco Unified Communications Manager database, but
there is no button on the phone with which calls can be answered. These directory numbers should
be removed from the phone and deleted if necessary.
"Creating a New Configuration File" section on page 7-4
Reset the phone manually.
If the phone does not start up properly, power up the phone with the handset off-hook. Then the
phone is powered up in this way, it attempts to launch a backup software image.
"Adding Phones to the Cisco Unified
to ensure that the phone has been added to the
Licenses for Phones
7-10.
Resolving Startup Problems
2-11.
for assistance.
section in the Cisco Unified
"Using Cisco
7-5