docker-minecraft-server/minecraft-server

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 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

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

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
• 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 ...

Healthcheck

This image contains Dinnerbone's mcstatus and uses its ping 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

Finally, since mcstatus is on the PATH you can exec into the container and use mcstatus directly and invoke any of its other commands:

> docker exec mc mcstatus localhost status
version: v1.12 (protocol 335)
description: "{u'text': u'A Minecraft Server Powered by Docker'}"
players: 0/20 No players online

Running a Forge Server

Enable Forge server mode by adding a -e TYPE=FORGE to your command-line. By default the container will run the RECOMMENDED version of Forge server but you can also choose to run a specific version with -e FORGEVERSION=10.13.4.1448.

$ docker run -d -v /path/on/host:/data -e VERSION=1.7.10 \
    -e TYPE=FORGE -e FORGEVERSION=10.13.4.1448 \
    -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
└── ...

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.

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 enviroment variables.

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

There are some limitations to what characters you can use.

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

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"
      CONSOLE: "false"
      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: "ug23u3bg39o-ogADSs"
    restart: always
  rcon:
    image: itzg/rcon
    ports:
      - "4326:4326"
      - "4327:4327"
    volumes:
      - "rcon:/opt/rcon-web-admin/db"

volumes:
  mc:
  rcon:

Running a Bukkit/Spigot server

Enable Bukkit/Spigot server mode by adding a -e TYPE=BUKKIT -e VERSION=1.8 or -e TYPE=SPIGOT -e VERSION=1.8 to your command-line.

docker run -d -v /path/on/host:/data \
    -e TYPE=SPIGOT -e VERSION=1.8 \
    -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

NOTE: to avoid pegging the CPU when running Spigot, you will need to pass --noconsole at the very end of the command line and not use -it. For example,

docker run -d -v /path/on/host:/data \
    -e TYPE=SPIGOT -e VERSION=1.8 \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server --noconsole

You can install Bukkit plugins in two ways...

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 plugins to the /path/on/host/plugins folder you chose. From the example above, the /path/on/host folder contents look like:

/path/on/host
├── plugins
│   └── ... INSTALL PLUGINS HERE ...
├── ops.json
├── server.properties
├── whitelist.json
└── ...

If you add plugins 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 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.

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.

Building an image with plugins

You can also create your own Docker images by extending the itzg/minecraft-server image. The image contains an ONBUILD trigger that will copy a plugins.yml file from you build directory and download any plugins specified in it.

You can read about the ToF-BuildTools and how to use them here.

You can also find an example with a custom image in the examples dir.

Running a PaperSpigot server

Enable PaperSpigot server mode by adding a -e TYPE=PAPER -e VERSION=1.9.4 to your command-line.

docker run -d -v /path/on/host:/data \
    -e TYPE=PAPER -e VERSION=1.9.4 \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

NOTE: to avoid pegging the CPU when running PaperSpigot, you will need to pass --noconsole at the very end of the command line and not use -it. For example,

docker run -d -v /path/on/host:/data \
    -e TYPE=PAPER -e VERSION=1.9.4 \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server --noconsole

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

• -e PAPER_DOWNLOAD_URL=

You can install Bukkit plugins in two ways...

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

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 plugins to the /path/on/host/plugins folder you chose. From the example above, the /path/on/host folder contents look like:

/path/on/host
├── plugins
│   └── ... INSTALL PLUGINS HERE ...
├── ops.json
├── server.properties
├── whitelist.json
└── ...

If you add plugins 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 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.

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 a Server with a Feed-The-Beast (FTB) / CurseForge modpack

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

You need to specify a modpack to run, using the FTB_SERVER_MOD or CF_SERVER_MOD environment variable. An FTB/CurseForge server modpack is available together with its respective client modpack on https://www.feed-the-beast.com under "Additional Files." Similar you can locate the modpacks for CurseForge at https://minecraft.curseforge.com/modpacks .

There are a couple of options for obtaining an FTB/CurseForge modpack. One options is that you can pre-download the server modpack and copy the modpack to the /data directory (see "Attaching data directory to host filesystem”).

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

docker run -d -v /path/on/host:/data -e TYPE=FTB \
    -e FTB_SERVER_MOD=FTBPresentsSkyfactory3Server_3.0.6.zip \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

Instead of pre-downloading a modpack from the FTB/CurseForge site, you can you set FTB_SERVER_MOD (or CF_SERVER_MOD) to the server URL of a modpack, such as

docker run ... \
  -e TYPE=FTB \
  -e FTB_SERVER_MOD=https://www.feed-the-beast.com/projects/ftb-infinity-lite-1-10/files/2402889

or for a CurseForce modpack:

docker run ... \
  -e TYPE=CURSEFORGE \
  -e CF_SERVER_MOD=https://minecraft.curseforge.com/projects/enigmatica2expert/files/2663153/download

Using the /data volume

You must use a persistent /data mount for this type of server.

To do this, you will need to attach the container's /data directory (see "Attaching data directory to host filesystem”).

If the modpack is updated and you want to run the new version on your server, you stop and remove the container:

docker stop mc
docker rm mc

Do not erase anything from your /data directory (unless you know of specific mods that have been removed from the modpack). Download the updated FTB server modpack and copy it to /data. Start a new container with FTB_SERVER_MOD specifying the updated modpack file.

$ docker run -d -v /path/on/host:/data -e TYPE=FTB \
    -e FTB_SERVER_MOD=FTBPresentsSkyfactory3Server_3.0.7.zip \
    -p 25565:25565 -e EULA=TRUE --name mc itzg/minecraft-server

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

Using a client-made curseforge modpack

If you use something like curseforge, you may end up creating/using modpacks that do not contain server mod jars. Instead, the curseforge setup has manifest.json files, which will show up under /data/FeedTheBeast/manifest.json.

To use these packs you will need to:

• Specify the manifest location with env var MANIFEST=/data/FeedTheBeast/manifest
• Pick a relevant ServerStart.sh and potentially settings.cfg and put them in /data/FeedTheBeast

An example of the latter would be to use https://github.com/AllTheMods/Server-Scripts There, you'll find that all you have to do is put ServerStart.sh and settings.cfg into /data/FeedTheBeast, taking care to update settings.cfg to specify your desired version of minecraft and forge. You can do this in the cli with something like:

$ wget https://raw.githubusercontent.com/AllTheMods/Server-Scripts/master/ServerStart.sh
$ wget https://raw.githubusercontent.com/AllTheMods/Server-Scripts/master/settings.cfg
$ vim settings.cfg #update the forge version to the one you want. Your manifest.json will have it
$ chmod +x ServerStart.sh
$ docker run -itd --name derpcraft \
  -e MANIFEST=/data/FeedTheBeast/manifest.json \
  -v $PWD/ServerStart.sh:/data/FeedTheBeast/ServerStart.sh \
  -v $PWD/settings.cfg:/data/FeedTheBeast/settings.cfg \
  -e VERSION=1.12.2\
  -e TYPE=CURSEFORGE\
  -e CF_SERVER_MOD=https://minecraft.curseforge.com/projects/your_amazing_modpack/files/2670435/download\
  -p 25565:25565\
  -e EULA=TRUE\
  --restart=always\
  itzg/minecraft-server

Note the CF_SERVER_MOD env var should match the url to download the modpack you are targeting.

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 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.

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

The server port can be set like:

docker run -d -e SERVER_PORT=25565 ...

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

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;'

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. This will be downloaded, and unpacked in the /data directory; if it does not contain a subdirectory called world/ then it will be searched for a file level.dat and the containing subdirectory renamed to world. This means that most of the archived Minecraft worlds downloadable from the Internet will already be in the correct format.

The ZIP file may also contain a server.properties file and modules directory, if required.

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

NOTE: Unless you also mount /data as an external volume, this world will be deleted when the container is deleted.

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

Cloning world from a container path

The WORLD option can also be used to reference a directory that will be used as a source to clone 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 

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

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].

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.

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