To become a hero to my children and, to a lesser extent, their friends. This will be accomplished by being able to run multiple minecraft servers.
This project was sponsored by my employer, StackEngine as part of the Docker 101 series of tutorials. If you would like details about how and why this container is constructed the way it is, see the supporting blog post
The run command below will get you the latest snapshot my kids have asked me to containerize.
You can check Docker Hub for an up to date list of tags, but here is partial immedate gratification:
- 1.8.6-a
- snapshot-1.9.0-15w41a
docker run \
--detach \
--publish 25565:25565 \
behemphi/docker-minecraft:latest
The above is a great way to run a server quick and dirty, however it is very prone to data loss. This tends to interfere with hero status, so if you are ready for some more advanced Docker see the Data Management section below.
If you were to upgrade from 1.8.6 to 1.8.8 by simply rebuilding the image with the new 1.8.8 binary and starting a new container, you would not have your data. It's in the old container.
Docker suggests several ways to deal with this. Here are the specific mechanics of the dedicated data volume method:
Before starting the Minecraft container as above, first start a container that will serve as just a data volume:
docker run \
--detach \
--p 25565:25565 \
--volume /minecraft/WORLD \
--name minecraft-data
behemphi/minecraft-1.8.6
Note that this command exposes /minecraft/WORLD as a volume and gives the
running container a specific name minecraft-data.
Now stop (not remove) the minecraft-data container. It need not be running
to store data and this keeps you from incurring all the weight of Java there.
docker stop minecraft-data
Now start the Mincraft server:
docker run \
--detach \
--publish 25565:25565 \
--volumes-from minecraft-data
behemphi/docker-minecraft:latest
Note that we are telling this container to using volumes defined in the
previously started/stopped minecraft-data.
Now your data is (somewhat) safe in the data volume.
Of course, the first question you will get after starting a server is, "Mom/Dad can you make it so I can play in creative mode?" After that it will be "Can I change the message of the day," or "Can we run a snapshot?"
Now that Minecraft is in a container, you can run multiple different kinds of server easily from the same machine. Here is an example command for starting a creative server:
docker run \
--detach \
--publish 22334:25565 \
--env GAMEMODE=1 \
--env FORCE_GAMEMODE=true \
--volumes-from minecraft-creative-data \
--name minecraft-creative-1.8.6
behemphi/docker-minecraft
The above command is how I run a creative server container. Things to note:
--publish- I needed a different port since the original (survival) is running on the standard port 25565--env GAMEMODE- sets the server property to creative (1)--env FORCE_GAMEMODE- enforces this always being a creative server when the client connects.--volumes-from- assumes you have created a dedicated data volume calledminecraft-creative-datathe same way we did above.
If all you want to do is run an available snapshot, you need only:
docker run \
--detach \
--publish 25565:25565 \
behemphi/docker-minecraft:snapshot-1.9.0-15w41a
You can go through the usual steps outlined above if you would like to keep your data in a dedicated volume.
Things get much more interesting if you would like to use the data from your existing world.
DO NOT point a snapshot at your existing data container. If there is a bug in the snapshot that corrupts data, then your data is gone. You've been warned.
Instead take a backup of the minecraft-data volume by following the directions
found toward the bottom of the page in the heading
Backup, restore, or migrate data volumes
Then follow the same steps in starting/stop the dedicated volume, and then the server container.
MIT