docker run -d --name=plex --net=host -v /etc/localtime:/etc/localtime:ro -v <path to plex library>:/config -v <path to media>:/data  -e PUID=996 -e PGID=996 -e PLEXPASS=1 -p 32400:32400 lonix/plex:1.2

You need to map

--net=host for streaming to work.
Port 32400 for plex web-app.
Mount /config for plex config files.
Mount /data for plex media files
Mount /etc/localhost for timesync (Not required)
PLEXPASS set to 1 for Plexpass version, UNSET for Public
GUID and GPID set toyou local plex user group (you may need to create a user on the host (named plex))

This container will update plex on each launch (if update found). It is based on phusion-baseimage with ssh removed. (use nsenter). If the app does not update to the latest version, i need to update a file on server, msg me at lonixx@gmail.com

Credits