systemctl start docker` instead.

3. Verify that the installation is successful by running the `hello-world` image:

   ```console
   $ sudo docker run hello-world
   ```

   This command downloads a test image and runs it in a container. When the
   container runs, it prints a confirmation message and exits.

You have now successfully installed and started Docker Engine.

{{% include "root-errors.md" %}}

#### Upgrade Docker Engine

To upgrade Docker Engine, follow the [installation instructions](#install-using-the-repository),
choosing the new version you want to install.

### Install from a package

If you can't use Docker's `rpm` repository to install Docker Engine, you can
download the `.rpm` file for your release and install it manually. You need to
download a new file each time you want to upgrade Docker Engine.

<!-- markdownlint-disable-next-line -->
1. Go to [{{% param "download-url-base" %}}/]({{% param "download-url-base" %}}/)
   and choose your version of SLES. Then browse to `s390x/stable/Packages/`
   and download the `.rpm` file for the Docker version you want to install.

2. Install Docker Engine, changing the following path to the path where you downloaded
   the Docker package.

   ```console
   $ sudo zypper install /path/to/package.rpm
   ```

   Docker is installed but not started. The `docker` group is created, but no
   users are added to the group.

3. Start Docker Engine.

   ```console
   $ sudo systemctl enable --now docker
   ```

   This configures the Docker systemd service to start automatically when you
   boot your system. If you don't want Docker to start automatically, use `sudo
   systemctl start docker` instead.

4. Verify that the installation is successful by running the `hello-world` image:

   ```console
   $ sudo docker run hello-world
   ```

   This command downloads a test image and runs it in a container. When the
   container runs, it prints a confirmation message and exits.

You have now successfully installed and started Docker Engine.

{{% include "root-errors.md" %}}

#### Upgrade Docker Engine

To upgrade Docker Engine, download the newer package files and repeat the
[installation procedure](#install-from-a-package), using `zypper -y upgrade`
instead of `zypper -y install`, and point to the new files.

{{% include "install-script.md" %}}

## Uninstall Docker Engine

1. Uninstall the Docker Engine, CLI, containerd, and Docker Compose packages:

   ```console
   $ sudo zypper remove docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin docker-ce-rootless-extras
   ```

2. Images, containers, volumes, or custom configuration files on your host
   aren't automatically removed. To delete all images, containers, and volumes:

   ```console
   $ sudo rm -rf /var/lib/docker
   $ sudo rm -rf /var/lib/containerd
   ```

You have to delete any edited configuration files manually.

## Next steps

- Continue to [Post-installation steps for Linux](linux-postinstall.md).