LinuxGSM_

Game Servers

Jedi Knight: Jedi Academy server

Run a Jedi Knight: Jedi Academy dedicated server with LinuxGSM, in Docker or directly on Linux.

jk3server Docker jk3

Run with Docker

First install Docker Engine and the Compose plugin on your Linux host. Run the commands below from your project directory with a user allowed to access Docker; otherwise prefix Docker commands with sudo. The container manages its own linuxgsm user.

The jk3 image has LinuxGSM and every dependency for Jedi Knight: Jedi Academy already installed on Ubuntu 26.04. On first start it downloads the game server, then keeps it updated.

1. Create compose.yaml

compose.yaml
services:
  jk3server:
    image: ghcr.io/gameservermanagers/gameserver:jk3
    container_name: jk3server
    restart: unless-stopped
    network_mode: host
    volumes:
      - ./jk3server:/data
    environment:
      - UPDATE_CHECK=60

Also published on Docker Hub as gameservermanagers/gameserver:jk3. Prefer docker run? See Docker help.

2. Start it

shell
docker compose up -d
docker compose logs -f

The first start installs the server, which can take a while for large games. When it is ready the log shows the server details, including ports and passwords.

Ports

With network_mode: host the server uses the host's ports directly, so there is nothing to map. Open them in your firewall.

SettingDefault port
port29070

Defaults from the LinuxGSM config. Run details to see every port and its protocol.

Manage the server

Show details, ports and passwords
docker exec -it --user linuxgsm jk3server ./jk3server details
Open the live console (leave with CTRL+b then d)
docker exec -it --user linuxgsm jk3server ./jk3server console
Restart the game server
docker restart jk3server
Update the image
docker compose pull && docker compose up -d

Server files, configs and logs live in ./jk3server on the host: back up that directory. Docker help below covers permissions, environment variables and bridge networking.

Docker help

Images and tags

Images are built weekly and published to two registries. They are identical, so use whichever you prefer.

RegistryImage
GitHub Container Registryghcr.io/gameservermanagers/gameserver:jk3
Docker Hubgameservermanagers/gameserver:jk3

The image uses the base OS LinuxGSM recommends for this game. You do not need to match it on the host.

Use docker run instead of Compose
shell
docker run -d \
  --name jk3server \
  --network host \
  --restart unless-stopped \
  -v "$PWD/jk3server:/data" \
  -e UPDATE_CHECK=60 \
  ghcr.io/gameservermanagers/gameserver:jk3
Data and permissions

Everything that should survive a container update lives in /data inside the container, which is ./jk3server on the host.

Path in /dataContents
serverfiles/The game server itself
config-lgsm/LinuxGSM config, including common.cfg
log/Script, console and game logs
data/LinuxGSM data and cache

The game server runs as the linuxgsm user, not root. On every start the container sets that user to UID and GID (both 1000 by default) and takes ownership of /data. If your host user has a different ID, set them to match so you can edit files on the host:

compose.yaml
environment:
      - UID=1001
      - GID=1001
Environment variables
VariableDefaultWhat it does
UPDATE_CHECK60Minutes between update checks, from 1 to 59, or 60 for hourly. 0 turns scheduled checks off.
UPDATE_ON_STARTtrueCheck for a game update every time the container starts.
VALIDATE_ON_STARTfalseRun a SteamCMD validate on start. Slow, but repairs broken files.
UID / GID1000User and group IDs the game server runs as.
LGSM_GITHUBBRANCHmasterLinuxGSM branch to run. Set develop to test unreleased fixes.
Updates and health checks

The game server updates itself. The container checks every UPDATE_CHECK minutes and on start. If an update is out, it stops the server, updates it and starts it again.

The image brings new LinuxGSM releases, dependency fixes and OS updates. Pull it now and then with docker compose pull && docker compose up -d.

The image runs LinuxGSM's monitor as the Docker health check every minute, so docker ps shows whether the game server is answering, not just whether the container is up.

Bridge networking

network_mode: host is the simplest choice: the game server uses the host's ports directly, the way it would without Docker, and query ports work without extra setup.

If you need bridge networking, publish each port the server uses. Run details to see them, then add them with the right protocol:

compose.yaml
ports:
      - "PORT:PORT/udp"
      - "PORT:PORT/tcp"

Bridge networking can hide the server's real IP from the game, which breaks some server browsers. Use host networking if players cannot find the server.

Troubleshooting
  • Permission denied in /data: set UID and GID to the owner of the host directory.
  • Server not listed in game: check the ports are open, use host networking, and add a GSLT if the game needs one.
  • Install fails at SteamCMD: the game may need a Steam login. Check the notes at the top of this page.
  • Will not start: stop the container, then run docker compose run --rm jk3server debug to see why.
  • Still stuck: run details and debug, then ask on Discord or GitHub Discussions with the output.

Install on Linux

Install directly on a server running Ubuntu 26.04.

1. Create a user and log in

Creating users and installing system packages require administrator privileges. From your administrator account, use sudo below (omit it if already root). Install curl, tar and an editor such as nano with your distribution's package manager first.

administrator shell
sudo adduser jk3server

Give the user a strong password, then switch to its login shell:

administrator shell
sudo su - jk3server

Run all remaining commands as jk3server from its home directory, without sudo. On Enterprise Linux, create the account with sudo useradd -m jk3server and set its password with sudo passwd jk3server instead of adduser.

2. Download LinuxGSM

shell
curl -Lo linuxgsm.sh https://linuxgsm.sh && chmod +x linuxgsm.sh && bash linuxgsm.sh jk3server

3. Install

shell
./jk3server install

LinuxGSM checks dependencies and installs the game files. If this user has sudo access, it can install missing packages when prompted. Otherwise, ask an administrator to install the packages listed by LinuxGSM, then rerun this command as jk3server. Running ./jk3server install as root only installs dependencies, not the game server.

4. Configure and start the server

Review your LinuxGSM settings in lgsm/config-lgsm/jk3server/jk3server.cfg (instance settings) or lgsm/config-lgsm/jk3server/common.cfg (shared settings). Do not edit _default.cfg, which LinuxGSM updates automatically. Game settings use a separate config file; run ./jk3server details to find its path. Once configured, start the server explicitly:

shell
./jk3server start

Common commands

Start the server
start
./jk3server start
Stop the server
stop
./jk3server stop
Restart the server
restart
./jk3server restart
Show details, ports and passwords
./jk3server details
Open the live console (leave with CTRL+b then d; CTRL+c stops the server)
./jk3server console
Run in the foreground to debug
./jk3server debug
Back up the whole server
./jk3server backup
List every command
./jk3server

Automate with cron

Restart the server if it crashes, apply game updates and keep LinuxGSM current. Add these with crontab -e.

crontab
*/5 * * * * /home/jk3server/jk3server monitor > /dev/null 2>&1
0 0 * * 0 /home/jk3server/jk3server update-lgsm > /dev/null 2>&1