Everything the container manages is located under the **container's** `/data` path, as shown here: ![](img/level-vs-world.drawio.png) !!! note The container path `/data` is pre-declared as a volume, so if you do nothing then it will be allocated as an anonymous volume. As such, it is subject to removal when the container is removed. ### Attaching data directory to host filesystem In most cases the easiest way to persist and work with the minecraft data files is to use the [volume mounting](https://docs.docker.com/storage/volumes/) `-v` argument to map a directory on your host machine to the container's `/data` directory. In the following example, the path `/home/user/minecraft-data` **must be** a directory on your host machine: -v /home/user/minecraft-data:/data ------------------------- ----- | | | +-- must always be /data | +-- replace with a directory on your host machine When attached in this way you can stop the server, edit the configuration under your attached directory and start the server again to pick up the new configuration. With Docker Compose, setting up a host attached directory is even easier since relative paths can be configured. For example, with the following `docker-compose.yml` Docker will automatically create/attach the relative directory `minecraft-data` to the container. ``` yaml title="docker-compose.yml" version: "3" services: mc: image: itzg/minecraft-server ports: - 25565:25565 environment: EULA: "TRUE" tty: true stdin_open: true restart: unless-stopped volumes: # attach a directory relative to the directory containing this compose file - ./minecraft-data:/data ``` !!! note if you have SELinux enabled, then you might need to add `:Z` to the end of volume mount specifications, [as described here](https://prefetch.net/blog/2017/09/30/using-docker-volumes-on-selinux-enabled-servers/). ### Converting anonymous `/data` volume to named volume If you had used the commands in the first section, without the `-v` volume attachment, then an anonymous data volume was created by Docker. You can later bring over that content to a named or host attached volume using the following procedure. !!! note In this example, it is assumed the original container was given a `--name` of "mc", so change the container identifier accordingly. You can also locate the Docker-managed directory from the `Source` field obtained from `docker inspect -f "{{json .Mounts}}"` First, stop the existing container: ``` shell docker stop mc ``` Use a temporary container to copy over the anonymous volume's content into a named volume, "mc" in this case: ``` shell docker run --rm --volumes-from mc -v mc:/new alpine cp -avT /data /new ``` Now you can recreate the container with any environment variable changes, etc by attaching the named volume created from the previous step: ``` shell docker run -d -it --name mc-new -v mc:/data -p 25565:25565 -e EULA=TRUE -e MEMORY=2G itzg/minecraft-server ``` ### Locating filesystem path of anonymous volume The `Source` field from the output of this command will show where the anonymous volume is mounted from: ``` shell docker inspect -f "{{json .Mounts}}" CONTAINER_NAME_OR_ID ``` !!! note On Windows with WSL the volumes path is `\\wsl$\docker-desktop-data\data\docker\volumes`