You must use these processes when upgrading Linux-based IP Office servers from pre-R11.1.3.x to R12.0.x or higher.

• Attempting to upgrade from pre-R11.1.3.x to R12.0.x or higher using the standard iso file transfer processes will fail and may cause loss of data and other issues.

The upgrade processes in this document are necessary because of the change of underlying Linux operating system from CentOS to Rocky Linux.

You must use the processes in this document for all types of Linux-based IP Office server.

• That include IP Office Application Servers.

• The processes in this document do not apply to IP500 V2 control units.

Always use the latest available R11.1.3.x and R12.0.x service packs. These will contain the latest changes for the upgrade process.

After upgrading, for further upgrades within R12.0.x, you can use the standard iso file transfer processes.