How to correctly backup GCEMS files when upgrading IMG software versions

Introduction:   

When upgrading the Dialogic IMG Integrated Media Gateway (IMG)  software to a newer build it is recommended that you back up certain Dialogc® Gate Control Element Management System (GCEMS) directories in order to preserve any existing configuration and license files.

Due to the way IMG software works, all installs must be done as root; however, some of the files written to during the install need to have the permissions of the excelsw user.  

This article describes how to backup the correct files without overwriting any of the permissions set on the directories and at the same time compresses the backup so it take up less space.

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