Cisco phones not updating
A guide for configuring a variety of Cisco IP Phone models (79XX series) to work with Asterisk PBX systems.
All configuration file examples are available as well.
This is also the case when dealing with Cisco phones.
By the way, when putting in an IP address via TUI, the “*” key can be used to put a period in an IP address. Firmware updates, line changes, or even ring cadence necessitate reboots. Or if the phone is running from an external power supply?
Available online and in PDF format: Online version: version: page documents how you configure a Cisco IP phone with Asterisk.
By default most Cisco Vo IP phones come configured for Call Manager, which uses the 'Skinny' protocol - SCCP.
Many of these values are set at the Cisco Unified Communications Manager (CUCM) level.
However, once common issue is the phone not being able to contact the CUCM server or the phone having the wrong address/TFTP server information from DHCP.