Pros and Cons
If you have an outdated operating system on your Plesk server, you should consider either upgrading the OS, or migrating to a server with a newer OS. Both options have pros and cons.
| Upgrade | Migration |
| Pros | Pros |
| – No need to update DNS for domains – No need to move over all your files – No need to re-configure your server | – A fresh, clean system – Can test things out and preview websites before updating DNS – Prevent possibility of downtime or broken system |
| Cons | Cons |
| – If you have an [unknown] infection or intrusion, it will remain – Possibility of remaining on older hardware – Possibility of things breaking | – More work – Updating DNS for all domains and subdomains – Also moving mailboxes and emails |
Can You Even Upgrade?
Some operating systems have in-place upgrade methods, but you have to be careful that it’s supported by Plesk. If Plesk has their own guides, methods, or tools you should always go to them first before running to OS specific fixes. Plesk only offers in-place upgrade solutions for CentOS, Debian, and Ubuntu. There are no in-place upgrade solutions offered or supported by Plesk for Windows Server.
CentOS
An in-place upgrade of any order of CentOS 6 -> CentOS 7 -> CentOS 8 is unsupported, and at the time of writing this, CentOS 6 and 8 are both past End of Life anyway. CentOS 7 end of life is next year in 2024.
CentOS moved over to the CentOS Stream versioning, with Stream 8 ending support next year, 2024, and Stream 9 being supported through 2027 (estimated).
Plesk does not provide a method or guide for upgrading from CentOS 6/7/8 to Stream 8/9. Instead, Plesk recommends converting the server in-place to AlmaLinux 8. Plesk supports AlmaLinux OS starting from Plesk Obsidian 18.0.35 and the conversion from CentOS 7 and CentOS 8 with Plesk to AlmaLinux 8 is supported, as well. As an alternative, Plesk also supports RockyLinux 8 and offers an in-place upgrade.
Other things to consider: AlmaLinux 8 Active Support (new features) ends May 2024, but Security/Maintenance Support lasts until March 2029. AlmaLinux 9 Active Support ends May 2027 (Security/Maintence until May 2032). Although AlmaLinux offers their own ‘ELevate’ tool for in-place upgrades, Plesk does not support this, and a migration would be recommended instead.
Follow this guide to convert CentOS 7 to AlmaLinux 8:
https://support.plesk.com/hc/en-us/articles/12388331912855-Does-Plesk-support-in-place-upgrade-from-CentOS-7-to-AlmaLinux-8-
Follow this guide to convert CentOS 8 to AlmaLinux 8:
https://support.plesk.com/hc/en-us/articles/12377014593303-Does-Plesk-support-AlmaLinux-as-an-alternative-to-CentOS-8-
Follow this guide to convert CentOS 8 to RockyLinux 8:
https://support.plesk.com/hc/en-us/articles/12387586927767-Does-Plesk-support-RockyLinux-as-an-alternative-to-CentOS-8-
Ubuntu/Debian
Plesk does support in-place upgrades for:
Ubuntu 20 > Ubuntu 22 with Plesk Obsidian 18.0.44 and above
Ubuntu 20 on ARM > Ubuntu 22 on ARM with Plesk Obsidian 18.0.46 and above
Ubuntu 18 > Ubuntu 20 with Plesk Obsidian 18.0.33 and above
Ubuntu 16 > Ubuntu 18 with Plesk Obsidian 18.0.30 and above
Debian 10 > Debian 11 with Plesk Obsidian 18.0.42 and above
Debian 9 > Debian 10 with Plesk Obsidian 18.0.30 and above
While Ubuntu 22.04 doesn’t reach End of Life until April 2032, Debian 11 reaches End of Life next year in July 2024. There is no supported in-place upgrade path for Debian 11 > Debian 12. For this, if you’re on Debian 11 or below, it’s preferable to migrate.
You can find the relevant instructions here:
https://support.plesk.com/hc/en-us/articles/12377714344983-How-to-perform-dist-upgrade-procedure-on-Linux-server-with-Plesk-
Migration
If you decide to go the route of migrating to a new Plesk server, there is a nifty Plesk Migrator tool that comes built-in to Plesk. Long story short: you open Plesk Migrator tool on the new source server, enter root credentials from destination server, and subscriptions, domains, files, and emails are migrated seamlessly. There’s a bit more to it, including preparing the source server to match dependencies and additional modules. Everything you need to know is in this migration guide:
https://support.plesk.com/hc/en-us/articles/12377889325719-Plesk-Migration-and-Transfer-Guide
For migrating to a new Plesk server, I highly recommend IONOS. Their new VPS are only $2/month and include Plesk for free.