Completing Docker Engine Installation, Upgrading, and Uninstalling

Replace `<VERSION_STRING>` with the desired version and then run the following command to install: ```console $ sudo dnf install docker-ce-<VERSION_STRING> docker-ce-cli-<VERSION_STRING> containerd.io docker-buildx-plugin docker-compose-plugin ``` This command installs Docker, but it doesn't start Docker. It also creates a `docker` group, however, it doesn't add any users to the group by default. {{< /tab >}} {{< /tabs >}} 2. 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. 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.  1. Go to [{{% param "download-url-base" %}}/]({{% param "download-url-base" %}}/) and choose your version of CentOS. Then browse to `x86_64/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 dnf 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 `dnf upgrade` instead of `dnf 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 dnf 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).

This section details completing the Docker Engine installation by starting the service and verifying the installation. It also guides on how to upgrade Docker Engine, whether it's through the repository method or manually using a downloaded `.rpm` package. Furthermore, it provides instructions for uninstalling Docker Engine, including removing the packages and manually deleting images, containers, and volumes.