(1) Just take a look at your Plex libraries (“Edit” → “Add folders”). This will tell you where your current setups expects your media
(2) Backup your PMS meta data:
It’s usually in /var/lib/plexmediaserver but you might have changed the location. Please review this guide and check if there is a systemd drop-in, i.e. an override.conf file on your system:
That’s what is most relevant for PMS and your mount points.
