1. Creating Custom Images With Image Builder
  2. About Image Builder
  3. Blueprints

Blueprints

Image Builder uses blueprints to create custom images.

A blueprint is the primary reference for creating custom images with Image Builder. A blueprint consists of block entries that define the specifications for the images. Block entries in a blueprint contain varied information but can be divided into two kinds: entries for packages and entries for other customizations.

Each block entry has a heading. The general headings are either [[packages]] if the block entry contains package information, or [[customizations]] if the block contains customizations that are unrelated to packages.

Package information specify packages to be downloaded for the image and include the following:

  • Packages: A package block entry requires the package name and version. The version format follows dnf version specifications. For example, the version for a major release is specified as n.n.n, such as 8.7.0. To specify the latest package version, enter an asterisk (*) in place of the version number. For a minor release, type major-nbr.*, such as 8.*.
  • Package groups: A package group block entry requires only the name of the package group. The information is entered under a [[groups]] heading.

Definitions in a block entry follow the convention parameter = "value". For more information about the contents of a blueprint, see Blueprint Format.

When you create images based on a blueprint, those images become associated with that blueprint in the Image Builder interface of the Cockpit web console.

To create or edit a blueprint, you can use any text editor. However, you must save the blueprint in Tom's Obvious Minimal Language (TOML) format.