I just inherited a Mastodon server that was on 3.5.1. I’ve got it upgraded to 3.5.15, which appears to the be latest version of the 3.5 branch. Which branch should I upgrade to now? 4.x, 4.1.x, or 4.2.x?
In my opinion the latest.
Make sure you read the full release notes of every intermediary release, as some contain upgrade steps (skipping those labelled ‘beta’ or ‘rc’)
When I say ‘read the full release notes’ please note, that the release list at https://github.com/mastodon/mastodon/releases only contains the beginning of each release note. You’ll need to click on the title of each release to read the full notes.
So: (1) read full release notes of all releases. (2) take a note of all steps required in each release. (3) check out 4.2.1. (4) execute all steps in order.
Don’t forget (0) make a backup though 😬
You may have to bite the bullet and trawl through the necessary incremental updates unless there’s a guide containing just the necessary steps.
You should be safe jumping to the latest version, just run db migrations and recompile from scratch the frontend assets. Of course, make a backup.
just go for the latest release, 4.2.x. check the release notes and follow all the steps. no need to do it step by step, just make sure you cover all the updates.