I can only really speak to your first point. When imported my existing library, I did it using Sonarr/Radarr as applicable. They have a manual import method, here’s a description of Sonarr’s.

Unfortunately that’ll probably work best if they’re formatted in a way Sonarr can readily recognize, something like /Season ##/S##E## - .ext. It may take a little work to get there, I found a program called mmv which helps out a lot. It allows you to move files that match a pattern, capture parts of pattern, and use that captured part to name the output file. That allowed me for format entire seasons at a time, but that method does rely on most files having similar names to begin with.

How did you setup file permissions for sonarr? I had trouble with it for the past few days

I’m in the same position as you, Linux server(s) on 24/7, and my torrent box just went bang, so could you point me to what and how you’ve setup your stack?

Have a Proxmox server and was thinking of creating a LXC, installing docker and having separate compose files for a arr stack rather than rebuilding the dedicated torrent box. Not a docker expert by any means

Problem I’ve got is that I’ve read so much about various ways of doing it, I’ve now stuck on which way would be best.

For importing movies: two ways, depending on the state of your existing media.

1. Point Radarr to your media. It might detect everything. Radarr will let you set rules for file name and structure. Follow jellyfin guidelines. Then let Radarr reorganize your files to the new structure. Then import to Jellyfin
2. If it’s very disorganized, you might have to organize it according to the jellyfin guides yourself, or script it if you can, before importing to jellyfin.