This is a super-simple way to get a DLNA image (photo) server up and running on your network. It uses the fantastic SimpleDLNA server at its core.
First build the container:
docker build -t sdlna .
Run it using a command similar to this:
docker run -d --name=mysdlna \
--net=host \
-p 39200:39200/tcp -p 1900:1900/udp \
-v /path/to/your/photos:/media \
-v /var/cache:/cache \
sdlna
The --net=host parameter is required to allow devices on
your network (such as Plex, Roku) to auto-detect the DLNA server.
If you plan to connect to the DLNA server directly, you may be able
to configure the network differently.
The TCP 39200 host port number is irrelevant; DLNA works on any high numbered port, so you may map that port to a different number on your host if you like. UDP port 1900 is the UPnP port; it must be mapped to port 1900 on the host for UPnP to work.
The directory you map to the /cache volume in the container will
end up containing a sdlna.sqlite file, which will contain the
DLNA server's metadata. This allows you to restart/rebuild the
container without losing the metadata. If you don't care about
keeping the metadata across container restarts, don't mount this
volume on your host.