engine/install: enable engine as system service on rpm installs

Unlike deb-based systems, installing an rpm doesn't automatically
start the Docker service, and starting the service doesn't make
it automatically start on (re)boot.

Update the instructions so that Docker is automatically started
on boot.

Signed-off-by: Sebastiaan van Stijn <[email protected]>

Author: thaJeztah

content/manuals/engine/install/centos.md

@@ -142,12 +142,18 @@ $ sudo yum-config-manager --add-repo {{% param "download-url-base" %}}/docker-ce
    {{< /tab >}}
    {{< /tabs >}}
 
-2. Start Docker.
+2. Start Docker Engine.
+
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 3. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 
@@ -188,12 +194,18 @@ download a new file each time you want to upgrade Docker Engine.
    Docker is installed but not started. The `docker` group is created, but no
    users are added to the group.
 
-3. Start Docker.
+3. Start Docker Engine.
+ 
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 4. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 

content/manuals/engine/install/fedora.md

@@ -139,12 +139,18 @@ $ sudo dnf-3 config-manager --add-repo {{% param "download-url-base" %}}/docker-
    {{< /tab >}}
    {{< /tabs >}}
 
-2. Start Docker.
+2. Start Docker Engine.
+
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 3. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 
@@ -185,19 +191,19 @@ download a new file each time you want to upgrade Docker Engine.
    Docker is installed but not started. The `docker` group is created, but no
    users are added to the group.
 
-3. Start Docker.
-
-   ```console
-   $ sudo systemctl start docker
-   ```
+3. Start Docker Engine.
 
-4. Make Docker start automatically after reboot.
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl enable docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
-5. Verify that the Docker Engine installation is successful by running the
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
+4. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 
    ```console

content/manuals/engine/install/rhel.md

@@ -143,12 +143,18 @@ $ sudo yum-config-manager --add-repo {{% param "download-url-base" %}}/docker-ce
    {{< /tab >}}
    {{< /tabs >}}
 
-2. Start Docker.
+2. Start Docker Engine.
+
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 3. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 
@@ -205,12 +211,18 @@ download a new file each time you want to upgrade Docker Engine.
    Docker is installed but not started. The `docker` group is created, but no
    users are added to the group.
 
-6. Start Docker.
+6. Start Docker Engine.
+
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 7. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 

content/manuals/engine/install/sles.md

@@ -162,12 +162,18 @@ $ sudo zypper addrepo {{% param "download-url-base" %}}/docker-ce.repo
    {{< /tab >}}
    {{< /tabs >}}
 
-2. Start Docker.
+2. Start Docker Engine.
+
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 3. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.
 
@@ -208,12 +214,18 @@ download a new file each time you want to upgrade Docker Engine.
    Docker is installed but not started. The `docker` group is created, but no
    users are added to the group.
 
-3. Start Docker.
+3. Start Docker Engine.
+
+   Start the Docker Engine and containerd as a systemd service that will launch
+   on boot:
 
    ```console
-   $ sudo systemctl start docker
+   $ sudo systemctl enable --now containerd docker
    ```
 
+   If you prefer Docker to only start manually, use `sudo systemctl start docker`
+   instead, which runs it only for the current session.
+
 4. Verify that the Docker Engine installation is successful by running the
    `hello-world` image.