Chapter 4. Embedding in a RHEL for Edge image for offline use

Procedure

1. Use the following example to create your blueprint:

   Image Builder blueprint example

   cat > minimal-microshift.toml <<EOF
   name = "minimal-microshift"
   
   description = ""
   version = "0.0.1"
   modules = []
   groups = []
   
   [[packages]]
   name = "microshift"
   version = "*"
   
   [customizations.services]
   enabled = ["microshift"]
   EOF

   Note

   The wildcard * in the commands uses the latest MicroShift RPMs. If you need a specific version, substitute the wildcard for the version you want. For example, insert 4.14.1 to download the MicroShift 4.14.1 RPMs.

2. Add the blueprint to the Image Builder by running the following command:

   $ sudo composer-cli blueprints push minimal-microshift.toml

Verification

1. Verify the Image Builder configuration listing only MicroShift packages by running the following command:

   $ sudo composer-cli blueprints depsolve minimal-microshift | grep microshift

   Example output

   blueprint: minimal-microshift v0.0.1
       microshift-greenboot-4.13.1-202305250827.p0.g4105d3b.assembly.4.13.1.el9.noarch
       microshift-networking-4.13.1-202305250827.p0.g4105d3b.assembly.4.13.1.el9.x86_64
       microshift-release-info-4.13.1-202305250827.p0.g4105d3b.assembly.4.13.1.el9.noarch
       microshift-4.13.1-202305250827.p0.g4105d3b.assembly.4.13.1.el9.x86_64
       microshift-selinux-4.13.1-202305250827.p0.g4105d3b.assembly.4.13.1.el9.noarch

2. Optional: Verify the Image Builder configuration listing all components to be installed by running the following command:

   $ sudo composer-cli blueprints depsolve minimal-microshift

Procedure

1. Start an ostree container image build by running the following command:

   $ BUILDID=$(sudo composer-cli compose start-ostree --ref "rhel/{op-system-version-major}/$(uname -m)/edge" <microshift_blueprint> edge-container | awk '{print $2}') 1

   1

   Replace <microshift_blueprint> with the name of your blueprint.

   This command also returns the identification (ID) of the build for monitoring.

2. You can check the status of the build periodically by running the following command:

   $ sudo composer-cli compose status

   Example output of a running build

   ID                                     Status     Time                     Blueprint                 Version   Type               Size
   cc3377ec-4643-4483-b0e7-6b0ad0ae6332   RUNNING    Wed Jun 7 12:26:23 2023  microshift_blueprint      0.0.1     edge-container

   Example output of a completed build

   ID                                     Status     Time                      Blueprint              Version   Type               Size
   cc3377ec-4643-4483-b0e7-6b0ad0ae6332   FINISHED   Wed Jun 7 12:32:37 2023   microshift_blueprint   0.0.1     edge-container

   Note

   You can use the watch command to monitor your build if you are familiar with how to start and stop it.

3. Download the container image using the ID and get the image ready for use by running the following command:

   $ sudo composer-cli compose image ${BUILDID}

4. Change the ownership of the downloaded container image to the current user by running the following command:

   $ sudo chown $(whoami). ${BUILDID}-container.tar

5. Add read permissions for the current user to the image by running the following command:

   $ sudo chmod a+r ${BUILDID}-container.tar

6. Bootstrap a server on port 8085 for the ostree container image to be consumed by the ISO build by completing the following steps:

   1. Get the IMAGEID variable result by running the following command:

      $ IMAGEID=$(cat < "./${BUILDID}-container.tar" | sudo podman load | grep -o -P '(?<=sha256[@:])[a-z0-9]*')

   2. Use the IMAGEID variable result to execute the podman command step by running the following command:

      $ sudo podman run -d --name=minimal-microshift-server -p 8085:8080 ${IMAGEID}

      This command also returns the ID of the container saved in the IMAGEID variable for monitoring.

7. Generate the installer blueprint file by running the following command:

   cat > microshift-installer.toml <<EOF
   name = "microshift-installer"
   
   description = ""
   version = "0.0.0"
   modules = []
   groups = []
   packages = []
   EOF