Chapter 6. Using RHEL image builder to create system images from different releases

Procedure

If you are creating a new blueprint

1. Create a blueprint. For example:

name = "<blueprint_name>"
description = "<image-description>"
version = "0.0.1"
modules = []
groups = []
distro = "<distro-version>"

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By setting the distro field to “rhel-88", you ensure that it always builds a RHEL 8.8 image, no matter which version is running on the host.

Note

If the distro field is blank, it uses the same distribution of the host.

If you are updating an existing blueprint

1. Save (export) the existing blueprint to a local text file:

# composer-cli blueprints save EXISTING-BLUEPRINT

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1. Edit the existing blueprint file with a text editor of your choice, setting the distro field with the distribution of your choice, for example:

   name = "blueprint_84"
   description = "A 8.8 base image"
   version = "0.0.1"
   modules = []
   groups = []
   distro = "rhel-88"

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2. Save the file and close the editor.

3. Push (import) the blueprint back into RHEL image builder:

   # composer-cli blueprints push EXISTING-BLUEPRINT.toml

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4. Start the image creation:

   # composer-cli compose start BLUEPRINT-NAME IMAGE-TYPE

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   Wait until the compose is finished.

5. Check the status of the compose:

   # composer-cli compose status

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   After the compose finishes, it shows a FINISHED status value. Identify the compose in the list by its UUID.

6. Download the resulting image file:

   # composer-cli compose image UUID

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   Replace UUID with the UUID value shown in the previous steps.