Updating Plesk - how to do it right?

Question

Plesk

Good day.
You need to update Plesk. At the moment, the version is 11.5.30, the new one is already 12.0.18. Everything is on Debian 6.0.10
How to properly update Plesk so that nothing crashes - a lot of mailboxes (a large number of letters), 15 domains.
Never done something like this. I would like to know what should be followed, and in general to explain to the teapot what needs to be done.
Sincerely.

Answer 1

Most importantly, when updating the Panel, use the Parallels Installer utility. The utility connects to the Parallels update server where Panel packages are stored, obtains the required packages, and updates them.
When upgrading to a new version of Panel, make sure you upgrade all installed components. This will avoid conflict between old and new components.