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+# Arma 3 server Dockerfile
+
+## Introduction
+
+This dockerfile install Steam CLI and download Arma 3 server content and execute it.
+The container needs two environment variables to work properly:
+```
+STEAM_LOGIN
+STEAM_PASSWORD
+```
+containing the login and password to connect to a steam account.
+Because it use a volume to store the Steam and Arma 3 data, you will need to create a directory on the host filesystem to bind the volume.
+
+## Building from source
+
+To build from source you need to clone the git repo and run docker build:
+```
+git clone https://github.com/poooldo/arma3server.git
+cd arma3server
+docker build -t arma3server .
+```
+
+## Running
+
+First, you need to create the mountpoint used by the docker volume (I use /home/steam but you can change this accordingly in the Dockerfile):
+```
+# mkdir /home/steam
+# chown 2000:2000 /home/steam/
+```
+
+**Note:** We use 2000 as uid/guid which is the same when creating the steam user in the container. We will need around 2GB of memory to download Arma 3 content.
+
+Run the container using root or sudo:
+```
+docker run -e STEAM_LOGIN='your_steam_login' -e STEAM_PASSWORD='your_steam_password' -p 0.0.0.0:2302:2302/udp -v /home/steam:/home/steam -d -t arma3server
+```
+
+After the first run, the arma3 won't be touched. To manually tells the container you want to update all ARMA3 data, just declare $ARMA3_UPDATE_DATA on the next container run.
+
+## Customizing server.cfg
+
+In this vanilla version, Arma 3 server.cfg is a basic configuration file. You need to define $ARMA3_SERVER_CFG to overload its behavior.
+
+You can also define $SERVER_UPDATE_PASSWORD when running the container to generate automatic random password for admin and command. These passwords will be printed into the logs.
+
+## Running Mods
+
+To create a new image running a specific mod:
+- create an image based on this one.
+- add a script setting up things for the mod (ADD mymod.sh /tmp/mymod.sh)
+- declare $MOD_SCRIPT pointing to the setup script (ENV MOD_SCRIPT /tmp/mymod.sh)
+- overload server.cfg by adding yours (ADD server.cfg /tmp/server.cfg)
+- install needed services (i.e. MySQL,...)
+
+As soon as AltisLife image is pushed, you'll got an example.
+
+## Logging
+
+All logs print out in stdout/stderr and are available via the docker logs command:
+```
+docker logs <CONTAINER_NAME>
+```
+
+If everything works fine (after start.sh has finished to download Steam and Arma 3), you should see something like:
+```
+15:36:29 Game Port: 2302, Steam Query Port: 2303
+15:36:29 Initializing Steam server - Game Port: 2302, Steam Query Port: 2303
+Arma 3 Console version 1.54 : port 2302
+15:36:30 Connected to Steam servers
+```
+
+## Versions
+
+- GNU/Linux Debian Jessie: **8.x**