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Phones and versions are connected through the phone's Firmware version field. A phone that has "3.2.X" version will look for the SIP application in the tftproot/polycom/3.2.X folder - the [MAC].cfg file is configured to accommodate this. Configuration files are kept in the tftproot folder just like before 4.6.0 Update 1.
Admins can deploy multiple (major) firmware versions. You can have a 3.1.X, a 3.2.X and a 4.0.X firmware deployed for the situation in which there are multiple phones with different firmware versions.
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Automatic migration
After updating to 4.6.0 Update 1 phones will reboot twice. The first time the [MAC].cfg will be changed in order to instruct the phone to contact the provisioning servlet. The provisioning servlet will read the correct firmware installed on the phone (using the User Agent header of the phone's request) and then via a sipXconfig REST service will update the phone's firmware version in the database. On second reboot sipXconfig will generate the correct config files which phones will pick up. Both reboots are scheduled after 1 minute to give phones time to register.
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