Plex¶

compose/nas/plex.yml

# Portainer stack: plex
services:
  plex:
    image: lscr.io/linuxserver/plex:latest
    container_name: plex
    network_mode: host                 # simplest for GDM discovery + remote access on 32400
    environment:
      - PUID=${PLEX_PUID}              # a separate "plex" DSM user, same group as the media user
      - PGID=${PGID}
      - TZ=${TZ}
      - VERSION=docker
      # - PLEX_CLAIM=${PLEX_CLAIM}     # only for the very first start; get one at https://plex.tv/claim (valid 4 min)
    volumes:
      - /volume1/docker/plex:/config
      - /volume1/data/media:/data/media
    # Optional (not deployed yet): transcode to RAM
    # tmpfs:
    #   - /transcode:size=4g
    restart: unless-stopped

Libraries: Movies → /data/media/movies, TV Shows → /data/media/tv. "Empty trash automatically after every scan" is ON.

Streaming tuning for a CPU with no hardware transcoding¶

The rule: make every client Direct Play or Direct Stream. The CPU can manage about one 720p transcode and no 4K transcodes (see Hardware). Upload bandwidth is plentiful (a fast connection), so the server should send the original file, not shrink it.

Server settings (Settings → Remote Access / Network / Transcoder / Library)¶

Setting	Value	Why
Remote Access	Manual port, forwarded on the router on 32400 (see Remote access)	Direct connection, not the relay
Internet upload speed	about 65% of the measured upload	Lets Plex know how much headroom there is
Limit remote stream bitrate	Original (no cap)	A 20 Mbps cap was forcing about 35 4K/high-bitrate movies into transcodes the CPU can't do
Remote streams allowed per user	2
Enable Relay	OFF	The relay is capped at 2 Mbps, so every relayed stream is a transcode
LAN Networks	`${LAN_SUBNET},172.16.0.0/12`	So Docker clients (Seerr, Tautulli) count as local
Transcoder quality	Prefer higher speed encoding	Brings the one possible 720p transcode above realtime
Maximum simultaneous video transcode	1	Two transcodes would starve each other
Use hardware acceleration	on (does nothing here, but it's harmless)
Video preview thumbnails, chapter thumbnails, loudness/music analysis	as a scheduled task (not "asap")	Keeps a new 4K import from eating the CPU during playback
Transcoder temp dir	default. Optional: tmpfs `/transcode` (commented out in the compose file)

Client settings (every remote device)¶

Remote/Internet streaming quality: Original / Maximum
Automatically adjust quality: OFF (when on, it always transcodes)
Play smaller videos at original quality: ON
iOS "Limit cellular data": raise it from the 0.7 Mbps default
Travelling: Download at Original quality before you leave
Apple TV: Home streaming Maximum. tvOS Match Content → Dynamic Range + Frame Rate ON. Wired Ethernet. Optionally use Infuse as the client (it plays DV P5, TrueHD/DTS and PGS natively).

Library side (Sonarr/Radarr/Bazarr)¶

Prefer 1080p H.264/HEVC. Block AV1 (the 1st-gen Apple TV 4K and the Atom can't decode it).
Set cutoffs so 4K fallbacks are replaced by 1080p (see Radarr).
Text subtitles over image subtitles (see Bazarr).

Plex is reachable from the internet

Keep PMS updated (the latest tag plus a re-pull, see Maintenance) and watch Plex's security advisories.