I have a NAS running Ubuntu Server 18.04 with minidlna. Minidlna has been unmaintained for a long time and now it kind of sucks. I read that 19.10 has an integrated dlna server, but I couldn't find any instructions on how to use it on Ubuntu Server without a GUI. I'm willing to upgrade to a non-LTS version if it gives me a better DLNA experience, but I'd like now if and how it's possible to use that feature without a GUI.
The DLNA server in question is Rygel, which is part of Gnome, which Ubuntu uses. Normally that might suggest you might need Gnome (and a graphical server), but you can —as far as I can see— run this headless, from a command line.
sudo apt install rygel # double-check what this is going to install before saying yes!
~/.config/rygel.conf based on
man rygel.conf to set your settings. The main one you'll want is the
uris setting, to define where your media is stored.
Then just run
rygel. You'd probably test it at this point before adding a systemd service to keep it alive.
Install 19.10 Desktop, a suitable host because "the base of both server/desktop is the same, difference being only packages installed.".
Install your preferred NAS package(s).