Understanding Phone Configuration Files - Cisco 7940G Administration Manual

Chapter 2 Preparing to Install the Cisco Unified IP Phone on Your Network

Understanding Phone Configuration Files

Configuration files for a phone are stored on the TFTP server and define parameters for connecting to
Cisco Unified Communications Manager. In general, any time you make a change in
Cisco Unified Communications Manager that requires the phone to be reset, a change is made to the
phone's configuration file automatically.
Configuration files also contain information about which image load the phone should be running. If this
image load differs from the one currently loaded on a phone, the phone contacts the TFTP server to
request the required load files. (These files are digitally signed to ensure the authenticity of the files'
source.)
In addition, if the device security mode in the configuration file is set to Authenticated and the CTL file
on the phone has a valid certificate for Cisco Unified Communications Manager, the phone establishes
a TLS connection to Cisco Unified Communications Manager. Otherwise, the phone establishes a TCP
connection.
Note If the device security mode in the configuration file is set to Authenticated or Encrypted, but the phone
has not received a CTL file, the phone will continuously try to obtain a CTL file so that it can register
securely.
If you configure security-related settings in Cisco Unified Communications Manager Administration,
the phone configuration file will contain sensitive information. To ensure the privacy of a configuration
file, you must configure it for encryption. For detailed information, refer to the "Configuring Encrypted
Phone Configuration Files" chapter in Cisco Unified Communications Manager Security Guide.A phone
requests a configuration file whenever it resets and registers with Cisco Unified Communications
Manager.
A phone accesses a default configuration file named XmlDefault.cnf.xml from the TFTP server when
the following conditions exist:
•
•
•
If auto registration is not enabled and the phone has not been added to the
Cisco Unified Communications Manager Database, the phone registration request will be rejected. In
this case, the phone will reset and attempt to register repeatedly.
If the phone has registered before, the phone will access the configuration file named
SEPmac_address.cnf.xml, where mac_address is the MAC address of the phone.
Cisco Unified IP Phone 7960G/7940G Administration Guide for Cisco Unified Communications Manager 7.0 (SIP)
OL-15499-01
You have enabled auto-registration in Cisco Unified Communications Manager
The phone has not been added to the Cisco Unified Communications Manager Database
The phone is registering for the first time
Understanding Phone Configuration Files
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