Chapter 13. Pushing a container to a registry and embedding it into an image

Procedure

1. Set up a registry-config.toml file to select the container provider. The credentials are optional.

   provider = "<container_provider>"
   [settings]
   tls_verify = false
   username = "<admin>"
   password = "<your_password>"

2. Create a blueprint in the .toml format. This is a blueprint for the container in which you install an nginx package into the blueprint.

   name = "simple-container"
   description = "Simple RHEL container"
   version = "0.0.1"
   [[packages]]
   name = "nginx"
   version = "*"

3. Build the container image, by passing the registry and the repository to the image-builder tool as arguments.

   # image-builder build --blueprint <simple-container> --extra-repo "quay.io:8080/<namespace>/<repository>" --extra-repo registry-config.toml

   Note

   Building the container image takes time because of resolving dependencies of the customized packages.

4. After the image build finishes, the container you created is available in quay.io.

Verification

1. Open quay.io and click Repository Tags. You can see details about the container you created, such as:

   • Last modified
   • Image size
   • The manifest ID that you can copy to the clipboard.
2. Copy the manifest ID value to build the image in which you want to embed a container.

Procedure

1. Create a blueprint to build a qcow2 image. The blueprint must contain the [[containers]] customization.

   name = "image"
   description = "A qcow2 image with a container"
   version = "0.0.1"
   distro = "rhel-10"
   [[packages]]
   name = "podman"
   version = "*"
   [[containers]]
   source = "registry.access.redhat.com/ubi10:8080/image/container/container-image@sha256:manifest-ID-from-Repository-tag: tag-version"
   name =  "source"
   tls-verify = true

2. Build the container image:

   # image-builder build qcow2 --blueprint <blueprint>

   Note

   Building the image takes time because it checks the container on quay.io registry.

   You can use the qcow2 image you created and downloaded to create a VM.

Verification

1. Locate the resulting qcow2 image.
2. Start the qcow2 image in a VM. See Creating a virtual machine from a KVM guest image.
3. The qemu wizard opens. Log in to the qcow2 image by entering the username and password. These can be the username and password you set up in the .qcow2 blueprint in the customizations.user section, or created at boot time with cloud-init.

4. Run the container image and open a shell prompt inside the container:

   # podman run -it registry.access.redhat.com/ubi10:8080/<organization>/<repository>/bin/bash/

   registry.access.redhat.com is the target registry, <organization> is the organization, and repository is the location to push the container when it finishes building.

5. Check that the packages you added to the blueprint are available:

   # type -a nginx

   The output shows you the nginx package path.