Before performing the Plesk upgrade you must backup your Plesk 5.0.x server. To backup your Plesk 5.0.x server follow these steps:
This backup procedure may require a huge amount of storage space. Another good way to back up the Plesk server is to make a full backup of the system.
Stop Plesk services. Stop as many services as possible in your system (if you access server locally, you may stop inetd.).
Make copies of the following files and directories (you may use TAR):
All file attributes must be preserved.
If you cannot backup the complete /usr, you should backup the following files and directories:
After completing the backup, run the Plesk self-extracting script to update your Plesk 5.0.x software to Plesk 6.0.
If the upgrade was not successfully completed, you should restore your previous installation.
Repeat step 1.
Replace files and directories pointed in step 2 with their backup copies.
Start the services you stopped in step 1.
If you used language pack for Plesk 5.0.x, then you will need to install the language pack for Plesk 6.0 after upgrade, for the proper localization. Any custom interface skins used for Plesk 5.0.x control panel will not work properly with Plesk 6.0, as the skins formats are incompatible.