In-place upgrade is performed within one server environment. To perform in-place upgrade:
OS should be supported by its vendor and Plesk;
Installed Plesk version should support upgrade to Plesk Obsidian.
The supported versions are:- Plesk Onyx 17.0
- Plesk Onyx 17.5
- Plesk Onyx 17.8
If requirements are met, proceed with the upgrade using method from this article.
If an earlier version is installed you can either upgrade to Plesk Onyx first or Upgrade by transfer.