I think you need to mount the directory first. I'm not aware that docker can directly mount volumes from another server.
Navidrome Music Server (Unofficial)
Navidrome is a free, open source web-based music collection server and streamer. It gives you freedom to listen to your music collection from any browser or mobile device. https://www.navidrome.org
This is an unofficial community. However, we adhear to the official Code Of Conduct set by the Navidrome project.
Thanks, do you know what the optimal way to do this on boot is? Or is it best just to do it manually?
I'm using NFS shares to mount remote directories. You'll find plenty of tutorials, I guess, but the general approach will be to export folders on the remote machine (/etc/exports) and then mount them, either manually or in /etc/fstab. This assumes you are using Linux, other OSs will be different or will use different protocols (Samba?). What's best is depending on your use case, but it's not hard to automatically mount shares...