docker-minecraft-server/README.md

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This docker image provides a Minecraft Server that will automatically download the latest stable version at startup. You can also run/upgrade to any specific version or the latest snapshot. See the Versions section below for more information.

To simply use the latest stable version, run

docker run -d -p 25565:25565 --name mc -e EULA=TRUE itzg/minecraft-server

where the standard server port, 25565, will be exposed on your host machine.

If you want to serve up multiple Minecraft servers or just use an alternate port, change the host-side port mapping such as

docker run -p 25566:25565 ...

will serve your Minecraft server on your host's port 25566 since the -p syntax is host-port:container-port.

Speaking of multiple servers, it's handy to give your containers explicit names using --name, such as

docker run -d -p 25565:25565 --name mc itzg/minecraft-server

With that you can easily view the logs, stop, or re-start the container:

docker logs -f mc
    ( Ctrl-C to exit logs action )

docker stop mc

docker start mc

Be sure to always include -e EULA=TRUE in your commands, as Mojang/Microsoft requires EULA acceptance.

Looking for a Bedrock Dedicated Server

For Minecraft clients running on consoles, mobile, or native Windows, you'll need to use this image instead:

itzg/minecraft-bedrock-server

Interacting with the server

RCON is enabled by default, so you can exec into the container to access the Minecraft server console:

docker exec -i mc rcon-cli

Note: The -i is required for interactive use of rcon-cli.

To run a simple, one-shot command, such as stopping a Minecraft server, pass the command as arguments to rcon-cli, such as:

docker exec mc rcon-cli stop

The -i is not needed in this case.

In order to attach and interact with the Minecraft server, add -it when starting the container, such as

docker run -d -it -p 25565:25565 --name mc itzg/minecraft-server

With that you can attach and interact at any time using

docker attach mc

and then Control-p Control-q to detach.

For remote access, configure your Docker daemon to use a tcp socket (such as -H tcp://0.0.0.0:2375) and attach from another machine:

docker -H $HOST:2375 attach mc

Unless you're on a home/private LAN, you should enable TLS access.

EULA Support

Mojang now requires accepting the Minecraft EULA. To accept add

    -e EULA=TRUE

such as

    docker run -d -it -e EULA=TRUE -p 25565:25565 --name mc itzg/minecraft-server

Timezone Configuration

You can configure the timezone to match yours by setting the TZ environment variable:

    -e TZ=Europe/London

such as:

    docker run -d -it -e TZ=Europe/London -p 25565:25565 --name mc itzg/minecraft-server

Or mounting /etc/timezone as readonly (not supported on Windows):

    -v /etc/timezone:/etc/timezone:ro

such as:

    docker run -d -it -v /etc/timezone:/etc/timezone:ro -p 25565:25565 --name mc itzg/minecraft-server

Attaching data directory to host filesystem

In order to readily access the Minecraft data, use the -v argument to map a directory on your host machine to the container's /data directory, such as:

docker run -d -v /path/on/host:/data ...

When attached in this way you can stop the server, edit the configuration under your attached /path/on/host and start the server again with docker start CONTAINERID to pick up the new configuration.

Versions

To use a different Minecraft version, pass the VERSION environment variable, which can have the value

  • LATEST (the default)
  • SNAPSHOT
  • or a specific version, such as "1.7.9"

For example, to use the latest snapshot:

docker run -d -e VERSION=SNAPSHOT ...

or a specific version:

docker run -d -e VERSION=1.7.9 ...

When using "LATEST" or "SNAPSHOT" an upgrade can be performed by simply restarting the container. During the next startup, if a newer version is available from the respective release channel, then the new server jar file is downloaded and used. NOTE: over time you might see older versions of the server jar remain in the /data directory. It is safe to remove those.

Running Minecraft server on different Java version

To use a different version of Java, please use a docker tag to run your Minecraft server.

Tag name Description Linux
latest Default. Uses Java version 8 Alpine Linux
adopt15 Uses Java version 15 from AdoptOpenJDK Alpine Linux
adopt14 Uses Java version 14 from AdoptOpenJDK Alpine Linux
adopt13 Uses Java version 13 from AdoptOpenJDK Alpine Linux
adopt11 Uses Java version 11 from AdoptOpenJDK Alpine Linux
openj9 Uses Eclipse OpenJ9 JVM Alpine Linux
openj9-nightly Uses Eclipse OpenJ9 JVM testing builds Alpine Linux
multiarch Uses Java version 8 latest update Debian Linux
multiarch-latest Uses Java version 15 latest update Debian Linux

For example, to use a Java version 13:

docker run --name mc itzg/minecraft-server:adopt13

Keep in mind that some versions of Minecraft server can't work on the newest versions of Java. Also, FORGE doesn't support openj9 JVM implementation.

Healthcheck

This image contains mc-monitor and uses its status command to continually check on the container's. That can be observed from the STATUS column of docker ps

CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                    PORTS                                 NAMES
b418af073764        mc                  "/start"            43 seconds ago      Up 41 seconds (healthy)   0.0.0.0:25565->25565/tcp, 25575/tcp   mc

You can also query the container's health in a script friendly way:

> docker container inspect -f "{{.State.Health.Status}}" mc
healthy

Some orchestration systems, such as Portainer, don't allow for disabling the default HEALTHCHECK declared by this image. In those cases you can approximate the disabling of healthchecks by setting the environment variable DISABLE_HEALTHCHECK to true.

Autopause

Description

There are various bug reports on Mojang about high CPU usage of servers with newer versions, even with few or no clients connected (e.g. this one, in fact the functionality is based on this comment in the thread).

An autopause functionality has been added to this image to monitor whether clients are connected to the server. If for a specified time no client is connected, the Java process is stopped. When knocking on the server port (e.g. by the ingame Multiplayer server overview), the process is resumed. The experience for the client does not change.

Of course, even loaded chunks are not ticked when the process is stopped.

From the server's point of view, the pausing causes a single tick to take as long as the process is stopped, so the server watchdog might intervene after the process is continued, possibly forcing a container restart. To prevent this, ensure that the max-tick-time in the server.properties file is set correctly. Non-vanilla versions might have their own configuration file, you might have to disable their watchdogs separately (e.g. PAPER Servers).

On startup the server.properties file is checked and, if applicable, a warning is printed to the terminal. When the server is created (no data available in the persistent directory), the properties file is created with the Watchdog disabled.

The utility used to wake the server (knock(d)) works at network interface level. So the correct interface has to be set using the AUTOPAUSE_KNOCK_INTERFACE variable when using non-default networking environments (e.g. host-networking, Portainer oder NAS solutions). See the description of the variable below.

A starting, example compose file has been provided in examples/docker-compose-autopause.yml.

Enabling Autopause

Enable the Autopause functionality by setting:

-e ENABLE_AUTOPAUSE=TRUE

The following environment variables define the behaviour of auto-pausing:

  • AUTOPAUSE_TIMEOUT_EST, default 3600 (seconds) describes the time between the last client disconnect and the pausing of the process (read as timeout established)
  • AUTOPAUSE_TIMEOUT_INIT, default 600 (seconds) describes the time between server start and the pausing of the process, when no client connects inbetween (read as timeout initialized)
  • AUTOPAUSE_TIMEOUT_KN, default 120 (seconds) describes the time between knocking of the port (e.g. by the main menu ping) and the pausing of the process, when no client connects inbetween (read as timeout knocked)
  • AUTOPAUSE_PERIOD, default 10 (seconds) describes period of the daemonized state machine, that handles the pausing of the process (resuming is done independently)
  • AUTOPAUSE_KNOCK_INTERFACE, default eth0
    Describes the interface passed to the knockd daemon. If the default interface does not work, run the ifconfig command inside the container and derive the interface receiving the incoming connection from its output. The passed interface must exist inside the container. Using the loopback interface (lo) does likely not yield the desired results.

Deployment Templates and Examples

Helm Charts

Examples

The examples directory also provides examples of deploying the itzg/minecraft-server Docker image.

Amazon Web Services (AWS) Deployment

If you're looking for a simple way to deploy this to the Amazon Web Services Cloud, check out the Minecraft Server Deployment (CloudFormation) repository. This repository contains a CloudFormation template that will get you up and running in AWS in a matter of minutes. Optionally it uses Spot Pricing so the server is very cheap, and you can easily turn it off when not in use.

Running a Forge Server

Enable Forge server mode by adding a -e TYPE=FORGE to your command-line.

The overall version is specified by VERSION, as described in the section above and will run the recommended Forge version by default. You can also choose to run a specific Forge version with FORGEVERSION, such as -e FORGEVERSION=14.23.5.2854.

$ docker run -d -v /path/on/host:/data \
    -e TYPE=FORGE \
    -e VERSION=1.12.2 -e FORGEVERSION=14.23.5.2854 \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

To use a pre-downloaded Forge installer, place it in the attached /data directory and specify the name of the installer file with FORGE_INSTALLER, such as:

$ docker run -d -v /path/on/host:/data ... \
    -e FORGE_INSTALLER=forge-1.11.2-13.20.0.2228-installer.jar ...

To download a Forge installer from a custom location, such as your own file repository, specify the URL with FORGE_INSTALLER_URL, such as:

$ docker run -d -v /path/on/host:/data ... \
    -e FORGE_INSTALLER_URL=http://HOST/forge-1.11.2-13.20.0.2228-installer.jar ...

In both of the cases above, there is no need for the VERSION or FORGEVERSION variables.

In order to add mods, you have two options.

Using the /data volume

This is the easiest way if you are using a persistent /data mount.

To do this, you will need to attach the container's /data directory (see "Attaching data directory to host filesystem”). Then, you can add mods to the /path/on/host/mods folder you chose. From the example above, the /path/on/host folder contents look like:

/path/on/host
├── mods
│   └── ... INSTALL MODS HERE ...
├── config
│   └── ... CONFIGURE MODS HERE ...
├── ops.json
├── server.properties
├── whitelist.json
├── worlds
│   └── ... PLACE MAPS IN THEIR OWN FOLDERS HERE ...
└── ...

Providing a presistent /data mount is a good idea, both to persist the game world and to allow for the manual configuration which is sometimes needed.

For instance, imagine a scenario when the initial launch has completed, but you now want to change the worldmap for your server.

Assuming you have a shared directory to your container, you can then (after first launch) drag and drop your premade maps or worlds into the \worlds\ directory. Note: each world should be placed in its own folder under the \worlds\ directory.

Once your maps are in the proper path, you can then specify which map the server uses by changing the level-name value in server.properties to match the name of your map.

If you add mods or make changes to server.properties while the container is running, you'll need to restart it to pick those up:

docker stop mc
docker start mc

Using separate mounts

This is the easiest way if you are using an ephemeral /data filesystem, or downloading a world with the WORLD option.

There are two additional volumes that can be mounted; /mods and /config. Any files in either of these filesystems will be copied over to the main /data filesystem before starting Minecraft. If you want old mods to be removed as the /mods content is updated, then add -e REMOVE_OLD_MODS=TRUE. If you are running a BUKKIT distribution this will affect all files inside the plugins/ directory. You can fine tune the removal process by specifing the REMOVE_OLD_MODS_INCLUDE and REMOVE_OLD_MODS_EXCLUDE variables. By default everything will be removed. You can also specify the REMOVE_OLD_MODS_DEPTH (default 16) variable to only delete files up to a certain level.

For example: -e REMOVE_OLD_MODS=TRUE -e REMOVE_OLD_MODS_INCLUDE="*.jar" -e REMOVE_OLD_MODS_DEPTH=1 will remove all old jar files that are directly inside the plugins/ or mods/ directory.

This works well if you want to have a common set of modules in a separate location, but still have multiple worlds with different server requirements in either persistent volumes or a downloadable archive.

You can specify the destination of the configs that are located inside the /config mount by setting the COPY_CONFIG_DEST variable. The configs are copied recursivly to the /data/config directory by default. If a file was updated directly inside the /data/* directoy and is newer than the file in the /config/* mount it will not be overriden.

For example: -v ./config:/config -e COPY_CONFIG_DEST=/data will allow you to copy over your bukkit.yml and so on directly into the server directory.

Replacing variables inside configs

Sometimes you have mods or plugins that require configuration information that is only available at runtime. For example if you need to configure a plugin to connect to a database, you don't want to include this information in your Git repository or Docker image. Or maybe you have some runtime information like the server name that needs to be set in your config files after the container starts.

For those cases there is the option to replace defined variables inside your configs with environment variables defined at container runtime.

If you set the enviroment variable REPLACE_ENV_VARIABLES to TRUE the startup script will go thru all files inside your /data volume and replace variables that match your defined environment variables. Variables that you want to replace need to be wrapped inside ${YOUR_VARIABLE} curly brackets and prefixed with a dollar sign. This is the regular syntax for enviromment variables inside strings or config files.

Optionally you can also define a prefix to only match predefined environment variables.

ENV_VARIABLE_PREFIX="CFG_" <-- this is the default prefix

If you want use file for value (like when use secrets) you can add suffix _FILE to your variable name (in run command).

There are some limitations to what characters you can use.

Type Allowed Characters
Name 0-9a-zA-Z_-
Value 0-9a-zA-Z_-:/=?.+

Variables will be replaced in files with the following extensions: .yml, .yaml, .txt, .cfg, .conf, .properties.

Specific files can be excluded by listing their name (without path) in the variable REPLACE_ENV_VARIABLES_EXCLUDES.

Paths can be excluded by listing them in the variable REPLACE_ENV_VARIABLES_EXCLUDE_PATHS. Path excludes are recursive. Here is an example:

REPLACE_ENV_VARIABLES_EXCLUDE_PATHS="/data/plugins/Essentials/userdata /data/plugins/MyPlugin"

Here is a full example where we want to replace values inside a database.yml.


---
database:
  host: ${CFG_DB_HOST}
  name: ${CFG_DB_NAME}
  password: ${CFG_DB_PASSWORD}

This is how your docker-compose.yml file could look like:

version: "3"
# Other docker-compose examples in /examples

services:
  minecraft:
    image: itzg/minecraft-server
    ports:
      - "25565:25565"
    volumes:
      - "mc:/data"
    environment:
      EULA: "TRUE"
      ENABLE_RCON: "true"
      RCON_PASSWORD: "testing"
      RCON_PORT: 28016
      # enable env variable replacement
      REPLACE_ENV_VARIABLES: "TRUE"
      # define an optional prefix for your env variables you want to replace
      ENV_VARIABLE_PREFIX: "CFG_"
      # and here are the actual variables
      CFG_DB_HOST: "http://localhost:3306"
      CFG_DB_NAME: "minecraft"
      CFG_DB_PASSWORD_FILE: "/run/secrets/db_password"
    restart: always
  rcon:
    image: itzg/rcon
    ports:
      - "4326:4326"
      - "4327:4327"
    volumes:
      - "rcon:/opt/rcon-web-admin/db"

volumes:
  mc:
  rcon:

secrets:
  db_password:
    file: ./db_password

The content of db_password:

ug23u3bg39o-ogADSs

Running a Bukkit/Spigot server

Enable Bukkit/Spigot server mode by adding a -e TYPE=BUKKIT or -e TYPE=SPIGOT to your command-line.

docker run -d -v /path/on/host:/data \
    -e TYPE=SPIGOT \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

If you are hosting your own copy of Bukkit/Spigot you can override the download URLs with:

  • -e BUKKIT_DOWNLOAD_URL=
  • -e SPIGOT_DOWNLOAD_URL=

You can build spigot from source by adding -e BUILD_FROM_SOURCE=true

If you have attached a host directory to the /data volume, then you can install plugins within the plugins subdirectory. You can also attach a /plugins volume. If you add plugins while the container is running, you'll need to restart it to pick those up.

Running a Paper server

Enable Paper server mode by adding a -e TYPE=PAPER to your command-line.

By default the container will run the latest build of Paper server but you can also choose to run a specific build with -e PAPERBUILD=205.

docker run -d -v /path/on/host:/data \
    -e TYPE=PAPER \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

If you are hosting your own copy of Paper you can override the download URL with:

  • -e PAPER_DOWNLOAD_URL=

An example compose file is provided at examples/docker-compose-paper.yml.

If you have attached a host directory to the /data volume, then you can install plugins via the plugins subdirectory. You can also attach a /plugins volume. If you add plugins while the container is running, you'll need to restart it to pick those up.

Running a Tuinity server

A Tuinity server, which is a fork of Paper aimed at improving server performance at high playercounts.

-e TYPE=TUINITY

NOTE only VERSION=LATEST is supported

Running a Magma server

A Magma server, which is a combination of Forge and PaperMC, can be used with

-e TYPE=MAGMA

NOTE there are limited base versions supported, so you will also need to set VERSION, such as "1.12.2"

Running a Mohist server

A Mohist server can be used with

-e TYPE=MOHIST

NOTE there are limited base versions supported, so you will also need to set VERSION, such as "1.12.2"

Running a Catserver type server

A Catserver type server can be used with

-e TYPE=CATSERVER

NOTE Catserver only provides a single release stream, so VERSION is ignored

Running a server with a Feed the Beast modpack

NOTE requires itzg/minecraft-server:multiarch image

Feed the Beast application modpacks are supported by using -e TYPE=FTBA (note the "A" at the end of the type). This server type will automatically take care of downloading and installing the modpack and appropriate version of Forge, so the VERSION does not need to be specified.

Environment Variables:

  • FTB_MODPACK_ID: required, the numerical ID of the modpack to install. The ID can be located by finding the modpack and using the "ID" displayed next to the name
  • FTB_MODPACK_VERSION_ID: optional, the numerical Id of the version to install. If not specified, the latest version will be installed. The "Version ID" can be obtained by drilling into the Versions tab and clicking a specific version.

Upgrading

If a specific FTB_MODPACK_VERSION_ID was not specified, simply restart the container to pick up the newest modpack version. If using a specific version ID, recreate the container with the new version ID.

Example

The following example runs the latest version of FTB Presents Direwolf20 1.12:

docker run -d --name mc-ftb -e EULA=TRUE \
  -e TYPE=FTBA -e FTB_MODPACK_ID=31 \
  -p 25565:25565 \
  itzg/minecraft-server:multiarch

Normally you will also add -v volume for /data since the mods and config are installed there along with world data.

Running a server with a CurseForge modpack

Enable this server mode by adding -e TYPE=CURSEFORGE to your command-line, but note the following additional steps needed...

You need to specify a modpack to run, using the CF_SERVER_MOD environment variable. A CurseForge server modpack is available together with its respective client modpack at https://www.curseforge.com/minecraft/modpacks .

Now you can add a -e CF_SERVER_MOD=name_of_modpack.zip to your command-line.

docker run -d -v /path/on/host:/data -e TYPE=CURSEFORGE \
    -e CF_SERVER_MOD=SkyFactory_4_Server_4.1.0.zip \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

If you want to keep the pre-download modpacks separate from your data directory, then you can attach another volume at a path of your choosing and reference that. The following example uses /modpacks as the container path as the pre-download area:

docker run -d -v /path/on/host:/data -v /path/to/modpacks:/modpacks \
    -e TYPE=CURSEFORGE \
    -e CF_SERVER_MOD=/modpacks/SkyFactory_4_Server_4.1.0.zip \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

Modpack data directory

By default, CurseForge modpacks are expanded into the sub-directory /data/FeedTheBeast and executed from there. (The default location was chosen for legacy reasons, when Curse and FTB were maintained together.)

The directory can be changed by setting CF_BASE_DIR, such as -e CF_BASE_DIR=/data.

Buggy start scripts

Some modpacks have buggy or overly complex start scripts. You can avoid using the bundled start script and use this image's standard server-starting logic by adding -e USE_MODPACK_START_SCRIPT=false.

Fixing "unable to launch forgemodloader"

If your server's modpack fails to load with an error like this:

unable to launch forgemodloader

then you apply a workaround by adding this to the run invocation:

-e FTB_LEGACYJAVAFIXER=true

Running a SpongeVanilla server

Enable SpongeVanilla server mode by adding a -e TYPE=SPONGEVANILLA to your command-line. By default the container will run the latest STABLE version. If you want to run a specific version, you can add -e SPONGEVERSION=1.11.2-6.1.0-BETA-19 to your command-line.

docker run -d -v /path/on/host:/data -e TYPE=SPONGEVANILLA \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

You can also choose to use the EXPERIMENTAL branch. Just change it with SPONGEBRANCH, such as:

$ docker run -d -v /path/on/host:/data ... \
    -e TYPE=SPONGEVANILLA -e SPONGEBRANCH=EXPERIMENTAL ...

Running a Fabric Server

Enable Fabric server mode by adding a -e TYPE=FABRIC to your command-line. By default, the container will run the latest version, but you can also choose to run a specific version with VERSION.

docker run -d -v /path/on/host:/data \
    -e TYPE=FABRIC \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

A specific installer version can be requested using FABRIC_INSTALLER_VERSION.

To use a pre-downloaded Fabric installer, place it in a directory attached into the container, such as the /data volume and specify the name of the installer file with FABRIC_INSTALLER, such as:

docker run -d -v /path/on/host:/data ... \
    -e FABRIC_INSTALLER=fabric-installer-0.5.0.32.jar ...

To download a Fabric installer from a custom location, such as your own file repository, specify the URL with FABRIC_INSTALLER_URL, such as:

docker run -d -v /path/on/host:/data ... \
    -e FABRIC_INSTALLER_URL=http://HOST/fabric-installer-0.5.0.32.jar ...

In order to add mods, you have two options:

Using the /data volume

This is the easiest way if you are using a persistent /data mount.

To do this, you will need to attach the container's /data directory (see "Attaching data directory to host filesystem”). Then, you can add mods to the /path/on/host/mods folder you chose. From the example above, the /path/on/host folder contents look like:

/path/on/host
├── mods
│   └── ... INSTALL MODS HERE ...
├── config
│   └── ... CONFIGURE MODS HERE ...
├── ops.json
├── server.properties
├── whitelist.json
└── ...

If you add mods while the container is running, you'll need to restart it to pick those up:

docker stop mc
docker start mc

Using separate mounts

This is the easiest way if you are using an ephemeral /data filesystem, or downloading a world with the WORLD option.

There are two additional volumes that can be mounted; /mods and /config. Any files in either of these filesystems will be copied over to the main /data filesystem before starting Minecraft.

This works well if you want to have a common set of modules in a separate location, but still have multiple worlds with different server requirements in either persistent volumes or a downloadable archive.

Deploying plugins from attached volume

There is one additional volume that can be mounted; /plugins. Any files in this filesystem will be copied over to the main /data/plugins filesystem before starting Minecraft. Set PLUGINS_SYNC_UPDATE=false if you want files from /plugins to take precedence over newer files in /data/plugins.

This works well if you want to have a common set of plugins in a separate location, but still have multiple worlds with different server requirements in either persistent volumes or a downloadable archive.

Running with a custom server JAR

If you would like to run a custom server JAR, set -e TYPE=CUSTOM and pass the custom server JAR via CUSTOM_SERVER. It can either be a URL or a container path to an existing JAR file.

If it is a URL, it will only be downloaded into the /data directory if it wasn't already. As such, if you need to upgrade or re-download the JAR, then you will need to stop the container, remove the file from the container's /data directory, and start again.

Force re-download of the server file

For VANILLA, FORGE, BUKKIT, SPIGOT, PAPER, CURSEFORGE, SPONGEVANILLA server types, set $FORCE_REDOWNLOAD to some value (e.g. 'true) to force a re-download of the server file for the particular server type. by adding a -e FORCE_REDOWNLOAD=true to your command-line.

For example, with PaperSpigot, it would look something like this:

docker run -d -v /path/on/host:/data \
    -e TYPE=PAPER -e FORCE_REDOWNLOAD=true \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

Using Docker Compose

Rather than type the server options below, the port mappings above, etc every time you want to create new Minecraft server, you can now use Docker Compose. Start with a docker-compose.yml file like the following:

minecraft-server:
  ports:
    - "25565:25565"

  environment:
    EULA: "TRUE"

  image: itzg/minecraft-server

  container_name: mc

  tty: true
  stdin_open: true
  restart: always

and in the same directory as that file run

docker-compose up -d

Now, go play...or adjust the environment section to configure this server instance.

Server configuration

By default the server configuration will be created and set based on the following environment variables, but only the first time the server is started. If the server.properties file already exists, the values in them will not be changed.

If you would like to override the server configuration each time the container starts up, you can set the OVERRIDE_SERVER_PROPERTIES environment variable like:

docker run -d -e OVERRIDE_SERVER_PROPERTIES=true ...

This will reset any manual configuration of the server.properties file, so if you want to make any persistent configuration changes you will need to make sure you have properly set the proper environment variables in your docker run command (described below).

Server name

The server name (e.g. for bungeecord) can be set like:

docker run -d -e SERVER_NAME=MyServer ...

Server port

WARNING: only change this value if you know what you're doing. It is only needed when using host networking and it is rare that host networking should be used. Use -p port mappings instead.

If you must, the server port can be set like:

docker run -d -e SERVER_PORT=25566 ...

however, be sure to change your port mapping accordingly and be prepared for some features to break.

Difficulty

The difficulty level (default: easy) can be set like:

docker run -d -e DIFFICULTY=hard ...

Valid values are: peaceful, easy, normal, and hard, and an error message will be output in the logs if it's not one of these values.

Whitelist Players

To whitelist players for your Minecraft server, pass the Minecraft usernames separated by commas via the WHITELIST environment variable, such as

docker run -d -e WHITELIST=user1,user2 ...

If the WHITELIST environment variable is not used, any user can join your Minecraft server if it's publicly accessible.

Op/Administrator Players

To add more "op" (aka adminstrator) users to your Minecraft server, pass the Minecraft usernames separated by commas via the OPS environment variable, such as

docker run -d -e OPS=user1,user2 ...

Server icon

A server icon can be configured using the ICON variable. The image will be automatically downloaded, scaled, and converted from any other image format:

docker run -d -e ICON=http://..../some/image.png ...

Rcon

To use rcon use the ENABLE_RCON and RCON_PASSORD variables. By default rcon port will be 25575 but can easily be changed with the RCON_PORT variable.

docker run -d -e ENABLE_RCON=true -e RCON_PASSWORD=testing

Query

Enabling this will enable the gamespy query protocol. By default the query port will be 25565 (UDP) but can easily be changed with the QUERY_PORT variable.

docker run -d -e ENABLE_QUERY=true

Max players

By default max players is 20, you can increase this with the MAX_PLAYERS variable.

docker run -d -e MAX_PLAYERS=50

Max world size

This sets the maximum possible size in blocks, expressed as a radius, that the world border can obtain.

docker run -d -e MAX_WORLD_SIZE=10000

Allow Nether

Allows players to travel to the Nether.

docker run -d -e ALLOW_NETHER=true

Announce Player Achievements

Allows server to announce when a player gets an achievement.

docker run -d -e ANNOUNCE_PLAYER_ACHIEVEMENTS=true

Enable Command Block

Enables command blocks

 docker run -d -e ENABLE_COMMAND_BLOCK=true

Force Gamemode

Force players to join in the default game mode.

  • false - Players will join in the gamemode they left in.

  • true - Players will always join in the default gamemode.

    docker run -d -e FORCE_GAMEMODE=false

Generate Structures

Defines whether structures (such as villages) will be generated.

  • false - Structures will not be generated in new chunks.

  • true - Structures will be generated in new chunks.

    docker run -d -e GENERATE_STRUCTURES=true

Hardcore

If set to true, players will be set to spectator mode if they die.

docker run -d -e HARDCORE=false

Snooper

If set to false, the server will not send data to snoop.minecraft.net server.

docker run -d -e SNOOPER_ENABLED=false

Max Build Height

The maximum height in which building is allowed. Terrain may still naturally generate above a low height limit.

docker run -d -e MAX_BUILD_HEIGHT=256

Max Tick Time

The maximum number of milliseconds a single tick may take before the server watchdog stops the server with the message, A single server tick took 60.00 seconds (should be max 0.05); Considering it to be crashed, server will forcibly shutdown. Once this criteria is met, it calls System.exit(1). Setting this to -1 will disable watchdog entirely

docker run -d -e MAX_TICK_TIME=60000

Spawn Animals

Determines if animals will be able to spawn.

docker run -d -e SPAWN_ANIMALS=true

Spawn Monsters

Determines if monsters will be spawned.

docker run -d -e SPAWN_MONSTERS=true

Spawn NPCs

Determines if villagers will be spawned.

docker run -d -e SPAWN_NPCS=true

Set spawn protection

Sets the area that non-ops can not edit (0 to disable)

docker run -d -e SPAWN_PROTECTION=0

View Distance

Sets the amount of world data the server sends the client, measured in chunks in each direction of the player (radius, not diameter). It determines the server-side viewing distance.

docker run -d -e VIEW_DISTANCE=10

Level Seed

If you want to create the Minecraft level with a specific seed, use SEED, such as

docker run -d -e SEED=1785852800490497919 ...

Game Mode

By default, Minecraft servers are configured to run in Survival mode. You can change the mode using MODE where you can either provide the standard numerical values or the shortcut values:

  • creative
  • survival
  • adventure
  • spectator (only for Minecraft 1.8 or later)

For example:

docker run -d -e MODE=creative ...

Message of the Day

The message of the day, shown below each server entry in the UI, can be changed with the MOTD environment variable, such as

docker run -d -e 'MOTD=My Server' ...

If you leave it off, a default is computed from the server type and version, such as

A Paper Minecraft Server powered by Docker

when TYPE is PAPER. That way you can easily differentiate between several servers you may have started.

The example shows how to specify a server message of the day that contains spaces by putting quotes around the whole thing.

PVP Mode

By default, servers are created with player-vs-player (PVP) mode enabled. You can disable this with the PVP environment variable set to false, such as

docker run -d -e PVP=false ...

Level Type and Generator Settings

By default, a standard world is generated with hills, valleys, water, etc. A different level type can be configured by setting LEVEL_TYPE to an expected type, such as

  • DEFAULT
  • FLAT
  • LARGEBIOMES
  • AMPLIFIED
  • CUSTOMIZED
  • BUFFET

Descriptions are available at the gamepedia.

When using a level type of FLAT, CUSTOMIZED, and BUFFET, you can further configure the world generator by passing custom generator settings. Since generator settings usually have ;'s in them, surround the -e value with a single quote, like below.

For example (just the -e bits):

-e LEVEL_TYPE=flat -e 'GENERATOR_SETTINGS=3;minecraft:bedrock,3*minecraft:stone,52*minecraft:sandstone;2;'

Custom Server Resource Pack

You can set a link to a custom resource pack and set it's checksum using the RESOURCE_PACK and RESOURCE_PACK_SHA1 options respectively, the default is blank:

docker run -d -e 'RESOURCE_PACK=http\://link.com/to/pack.zip?\=1' -e 'RESOURCE_PACK_SHA1=d5db29cd03a2ed055086cef9c31c252b4587d6d0'

NOTE: : and = must be escaped using \. The checksum plain-text hexadecimal.

World Save Name

You can either switch between world saves or run multiple containers with different saves by using the LEVEL option, where the default is "world":

docker run -d -e LEVEL=bonus ...

NOTE: if running multiple containers be sure to either specify a different -v host directory for each LEVEL in use or don't use -v and the container's filesystem will keep things encapsulated.

Downloadable world

Instead of mounting the /data volume, you can instead specify the URL of a ZIP file containing an archived world. It will be searched for a file level.dat and the containing subdirectory moved to the directory named by $LEVEL. This means that most of the archived Minecraft worlds downloadable from the Internet will already be in the correct format.

docker run -d -e WORLD=http://www.example.com/worlds/MySave.zip ...

NOTE: This URL must be accessible from inside the container. Therefore, you should use an IP address or a globally resolvable FQDN, or else the name of a linked container.

NOTE: If the archive contains more than one level.dat, then the one to select can be picked with WORLD_INDEX, which defaults to 1.

Cloning world from a container path

The WORLD option can also be used to reference a directory or zip file that will be used as a source to clone or unzip the world directory.

For example, the following would initially clone the world's content from /worlds/basic. Also notice in the example that you can use a read-only volume attachment to ensure the clone source remains pristine.

docker run ... -v $HOME/worlds:/worlds:ro -e WORLD=/worlds/basic

Overwrite world on start

The world will only be downloaded or copied if it doesn't exist already. Set FORCE_WORLD_COPY=TRUE to force overwrite the world on every server start.

Downloadable mod/plugin pack for Forge, Bukkit, and Spigot Servers

Like the WORLD option above, you can specify the URL of a "mod pack" to download and install into mods for Forge or plugins for Bukkit/Spigot. To use this option pass the environment variable MODPACK, such as

docker run -d -e MODPACK=http://www.example.com/mods/modpack.zip ...

NOTE: The referenced URL must be a zip file with one or more jar files at the top level of the zip archive. Make sure the jars are compatible with the particular TYPE of server you are running.

You may also download individual mods using the MODS environment variable and supplying the URL to the jar files. Multiple mods/plugins should be comma separated.

docker run -d -e MODS=https://www.example.com/mods/mod1.jar,https://www.example.com/mods/mod2.jar ...

Remove old mods/plugins

When the option above is specified (MODPACK) you can also instruct script to delete old mods/plugins prior to installing new ones. This behaviour is desirable in case you want to upgrade mods/plugins from downloaded zip file. To use this option pass the environment variable REMOVE_OLD_MODS="TRUE", such as

docker run -d -e REMOVE_OLD_MODS="TRUE" -e MODPACK=http://www.example.com/mods/modpack.zip ...

WARNING: All content of the mods or plugins directory will be deleted before unpacking new content from the MODPACK or MODS.

Online mode

By default, server checks connecting players against Minecraft's account database. If you want to create an offline server or your server is not connected to the internet, you can disable the server to try connecting to minecraft.net to authenticate players with environment variable ONLINE_MODE, like this

docker run -d -e ONLINE_MODE=FALSE ...

Allow flight

Allows users to use flight on your server while in Survival mode, if they have a mod that provides flight installed.

-e ALLOW_FLIGHT=TRUE|FALSE

Other server property mappings

Environment Variable Server Property
PLAYER_IDLE_TIMEOUT player-idle-timeout
BROADCAST_CONSOLE_TO_OPS broadcast-console-to-ops
BROADCAST_RCON_TO_OPS broadcast-rcon-to-ops
ENABLE_JMX enable-jmx-monitoring
SYNC_CHUNK_WRITES sync-chunk-writes
ENABLE_STATUS enable-status
ENTITY_BROADCAST_RANGE_PERCENTAGE entity-broadcast-range-percentage
FUNCTION_PERMISSION_LEVEL function-permission-level
NETWORK_COMPRESSION_THRESHOLD network-compression-threshold
OP_PERMISSION_LEVEL op-permission-level
PREVENT_PROXY_CONNECTIONS prevent-proxy-connections
USE_NATIVE_TRANSPORT use-native-transport
ENFORCE_WHITELIST enforce-whitelist

Miscellaneous Options

Running as alternate user/group ID

By default, the container will switch to user ID 1000 and group ID 1000; however, you can override those values by setting UID and/or GID as environmental entries, during the docker run command.

-e UID=1234
-e GID=1234

The container will also skip user switching if the --user/-u argument is passed to docker run.

Memory Limit

By default, the image declares a Java initial and maximum memory limit of 1 GB. There are several ways to adjust the memory settings:

  • MEMORY, "1G" by default, can be used to adjust both initial (Xms) and max (Xmx) memory settings of the JVM
  • INIT_MEMORY, independently sets the initial heap size
  • MAX_MEMORY, independently sets the max heap size

The values of all three are passed directly to the JVM and support format/units as <size>[g|G|m|M|k|K]. For example:

-e MEMORY=2G

JVM Options

General JVM options can be passed to the Minecraft Server invocation by passing a JVM_OPTS environment variable. Options like -X that need to proceed general JVM options can be passed via a JVM_XX_OPTS environment variable.

For some cases, if e.g. after removing mods, it could be necessary to startup minecraft with an additional -D parameter like -Dfml.queryResult=confirm. To address this you can use the environment variable JVM_DD_OPTS, which builds the params from a given list of values separated by space, but without the -D prefix. To make things running under systems (e.g. Plesk), which doesn't allow = inside values, a : (colon) could be used instead. The upper example would look like this: JVM_DD_OPTS=fml.queryResult:confirm, and will be converted to -Dfml.queryResult=confirm.

Enable Remote JMX for Profiling

To enable remote JMX, such as for profiling with VisualVM or JMC, add the environment variable ENABLE_JMX=true and add a port forwarding of TCP port 7091, such as:

-e ENABLE_JMX=true -p 7091:7091

Enable Aikar's Flags

Aikar has does some research into finding the optimal JVM flags for GC tuning, which becomes more important as more users are connected concurrently. The set of flags documented there can be added using

-e USE_AIKAR_FLAGS=true

When MEMORY is greater than or equal to 12G, then the Aikar flags will be adjusted according to the article.

Large page support can also be enabled by adding

-e USE_LARGE_PAGES=true

HTTP Proxy

You may configure the use of an HTTP/HTTPS proxy by passing the proxy's URL via the PROXY environment variable. In the example compose file it references a companion squid proxy by setting the equivalent of

-e PROXY=proxy:3128

Using "noconsole" option

Some older versions (pre-1.14) of Spigot required --noconsole to be passed when detaching stdin, which can be done by setting -e CONSOLE=FALSE.

Explicitly disable GUI

Some older servers get confused and think that the GUI interface is enabled. You can explicitly disable that by passing -e GUI=FALSE.

Stop Duration

When the container is signalled to stop, the Minecraft process wrapper will attempt to send a "stop" command via RCON or console and waits for the process to gracefully finish. By defaul it waits 60 seconds, but that duration can be configured by setting the environment variable STOP_DURATION to the number of seconds.

Running on RaspberryPi

To run this image on a RaspberryPi 3 B+, 4, or newer, use the image tag

itzg/minecraft-server:multiarch

NOTE: you may need to lower the memory allocation, such as -e MEMORY=750m