linux-dayz-docker

For 1.14 experimental, Linux support for servers was finally released. This is my half-assed attempt at creating a Docker container for running a (barebones) DayZ server.

Please keep in mind that this hasn't been tested with more than maybe 3 players and shouldn't be considered stable at all.
Crashes will occur, especially in experimental. Modding support probably isn't as stable as the Windows version etc.
This has all been written/tested by an amateur when it comes to DayZ server hosting, so not everything maybe be accurate.

Requirements

• System/server specifications matching the minimum requirements
  • During my testing I was running a VM with 6 dedicated threads and 32 GB RAM, on Debian 11 (though OS doesn't matter much).
  • By default the docker-compose.yml file limits the memory usage to 8 GB (mem_limit). Feel free to tweak as you see fit for your system.
  • From my experience: 3 threads/cores + 5 GB RAM available for the DayZ server is the absolute minimum.
• A Linux OS with bash installed, as I have no idea if my download.sh script is POSIX-compatible.
  • I use Debian 11 (Bullseye) as I'm writing, but other major OSes such as Ubuntu/CentOS will likely work just fine.
• Familiarity with the Linux commandline is a "must", as this isn't really intended for "Linux newbies".
• Server also needs Docker & Docker Compose installed
• Workshop content only: A Steam account with DayZ
  • It seems Steam does not allow downloading workshop content "anonymously", nor can you download workshop content for games you do not own on Steam.

Useful resources

1. DayZ Server Files Documentation on DayZ Forums
2. DayZ Server Configuration on Bohemia's wiki
   • Some duplicate information that's also included in #1.

Things that need to be done manually at the moment

• Mount the whitelist.txt / priority.txt files in the Docker Compose file
• Remote access via RCON isn't enabled by default. You can configure that by following the steps on Bohemia's wiki
  • Unless -bePath is used, the path for BattlEye should be: server_files/battleye/beserver_x64.cfg
  • You will also need to forward the RCON port in the docker-compose.yml file. By default I think it is 2303 (gamePort + 1 = rconPort)

Known issues

• Crashes. Server will often crash and "hang". I haven't been able to look into why, nor how to detect it. You'll just have to watch logs and manually restart accordingly (docker-compose down && docker-compose up -d).
  • There doesn't seem to be a good way to really detect it, as the server seems to still respond to "queries" and acting responsive, even if it has crashed.

Setup

1. Copy serverDZ.example.cfg to a new file called serverDZ.cfg. Edit the configuration options as you see fit.
   • Optional: Copy extra configuration options from the serverDZ_extra.example.cfg file into the serverDZ.cfg file you created.
2. Edit the file docker-compose.yml to match your server specs/needs.
   • Make sure all the paths (volumes), environment variables (for extra configuring) and memory limit matches what you want to limit your system to.
   • CPU_COUNT is practically "thread count" from what I understand. Easiest way to get that number is running nproc.
3. Run docker-compose up -d to start up the server. It will download the server files into server_files (unless changed in docker-compose.yml).
4. Optional: Run docker-compose logs -ft to watch the console/server logs. Hit CTRL+C to get out of the logs.

Once you're done with the server, run docker-compose down to shut the server/container down.
If you wanna boot it back up, just run docker-compose up -d again.

Server updates will run using SteamCMD every time the server is started back up, so it might take a few extra seconds.

Modifications to startup script

If you have modified the startup script (run_server.sh), you'll have to rebuild the container for script changes to apply.

Assuming you already have a running server while modifying the script:

1. docker-compose down to stop the server
2. docker-compose build to rebuild the container
3. docker-compose up -d to start the server back up again.

Workshop content

For workshop content, run ./download.sh -w WORKSHOP_ID_HERE, which will prompt you for your Steam username and a "Workshop mod name".
Specifically for DayZ workshop content you need a Steam account that owns DayZ.

• The "Workshop mod name" is used to create a folder within server_files/<Workshop Mod Name Here>, where mod files are later copied into.
• All workshop content will be downloaded to the workshop_mods folder.

I am not entirely sure if this is the correct method. I have literally zero experience with DayZ servers, so you might have to look into proper methods yourself.

Mod support

For mod support you will have to investigate yourself. You'll have to modify the launch options in run_server.sh, then rebuild the container using docker-compose build before (re)starting the server.

Thanks to

• Corbpie - For having a pretty solid blog post on how to set up a DayZ server on Windows. While I'm doing it on Linux, it was still useful for command-line flags and whatnot.