Composing a customized RHEL system image

Red Hat Enterprise Linux 9

Creating customized system images with RHEL image builder on Red Hat Enterprise Linux 9

Red Hat Customer Content Services

Abstract

RHEL image builder is a tool for creating deployment-ready customized system images: installation disks, virtual machines, cloud vendor-specific images, and others. By using RHEL image builder, you can create these images faster if compared to manual procedures, because it eliminates the specific configurations required for each output type. This document describes how to set up RHEL image builder and create images with it.

Making open source more inclusive

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Chapter 1. RHEL image builder description

To deploy a system, create a system image. To create RHEL system images, use the RHEL image builder tool. You can use RHEL image builder to create customized system images of RHEL, including system images prepared for deployment on cloud platforms. RHEL image builder automatically handles the setup details for each output type and is therefore easier to use and faster to work with than manual methods of image creation. You can access the RHEL image builder functionalities by using the command-line interface in the composer-cli tool, or the graphical user interface in the RHEL web console.

1.1. RHEL image builder terminology

RHEL image builder uses the following concepts:

Blueprint

A blueprint is a description of a customized system image. It lists the packages and customizations that will be part of the system. You can edit blueprints with customizations and save them as a particular version. When you create a system image from a blueprint, the image is associated with the blueprint in the RHEL image builder interface.

Create blueprints in the TOML format.

Compose
Composes are individual builds of a system image, based on a specific version of a particular blueprint. Compose as a term refers to the system image, the logs from its creation, inputs, metadata, and the process itself.
Customizations
Customizations are specifications for the image that are not packages. This includes users, groups, and SSH keys.

1.2. RHEL image builder output formats

RHEL image builder can create images in multiple output formats shown in the following table.

Table 1.1. RHEL image builder output formats

DescriptionCLI nameFile extension

QEMU Image

qcow2

.qcow2

Disk Archive

tar

.tar

Amazon Web Services

raw

.raw

Microsoft Azure

vhd

.vhd

Google Cloud Platform

gce

.tar.gz

VMware vSphere

vmdk

.vmdk

VMware vSphere

ova

.ova

Openstack

openstack

.qcow2

RHEL for Edge Commit

edge-commit

.tar

RHEL for Edge Container

edge-container

.tar

RHEL for Edge Installer

edge-installer

.iso

RHEL for Edge Raw Image

edge-raw-image

.raw.xz

RHEL for Edge Simplified Installer

edge-simplified-installer

.iso

RHEL for Edge AMI

edge-ami

.ami

RHEL for Edge VMDK

edge-vsphere

.vmdk

RHEL Installer

image-installer

.iso

Oracle Cloud Infrastructure

.oci

.qcow2

To check the supported types, run the command:

# composer-cli compose types

Chapter 2. Installing RHEL image builder

Before using RHEL image builder, you must install it.

2.1. RHEL image builder system requirements

The host that runs RHEL image builder must meet the following requirements:

Table 2.1. RHEL image builder system requirements

ParameterMinimal Required Value

System type

A dedicated host or virtual machine. Note that RHEL image builder is not supported in containers, including Red Hat Universal Base Images (UBI).

Processor

2 cores

Memory

4 GiB

Disk space

20 GiB of free space in the ` /var/cache/` filesystem

Access privileges

root

Network

Internet connectivity to the Red Hat Content Delivery Network (CDN).

Note

If you do not have internet connectivity, use RHEL image builder in isolated networks. For that, you must override the default repositories to point to your local repositories to not connect to Red Hat Content Delivery Network (CDN). Ensure that you have your content mirrored internally or use Red Hat Satellite.

2.2. Installing RHEL image builder

Install RHEL image builder to have access to all the osbuild-composer package functionalities.

Prerequisites

  • You are logged in to the RHEL host on which you want to install RHEL image builder.
  • The host is subscribed to Red Hat Subscription Manager (RHSM) or Red Hat Satellite.
  • You have enabled the BaseOS and AppStream repositories to be able to install the RHEL image builder packages.

Procedure

  1. Install RHEL image builder and other necessary packages:

    # dnf install osbuild-composer composer-cli cockpit-composer
    • osbuild-composer - A service to build customized RHEL operating system images.
    • composer-cli- This package enables access to the CLI interface.
    • cockpit-composer - This package enables access to the Web UI interface. The web console is installed as a dependency of the cockpit-composer package.
  2. Enable and start RHEL image builder socket:

    # systemctl enable --now osbuild-composer.socket
  3. If you want to use RHEL image builder in the web console, enable and start it.

    # systemctl enable --now cockpit.socket

    The osbuild-composer and cockpit services start automatically on first access.

  4. Load the shell configuration script so that the autocomplete feature for the composer-cli command starts working immediately without logging out and in:

    $ source /etc/bash_completion.d/composer-cli
  5. Restart the running osbuild-composer service on your RHEL host.

    # systemctl restart osbuild-composer

Verification

  • Verify that the installation works by running composer-cli:

    # composer-cli status show

Troubleshooting

You can use a system journal to track RHEL image builder activities. Additionally, you can find the log messages in the file.

  • To find the journal output for traceback, run the following commands:

    $ journalctl | grep osbuild
  • To show both remote or local workers:

    $ journalctl -u osbuild-worker*
  • To show the running services:

    $ journalctl -u osbuild-composer.service

Chapter 3. Configuring RHEL image builder repositories

To use RHEL image builder, you must ensure that the repositories are configured. You can use the following types of repositories in RHEL image builder:

Official repository overrides
Use these if you want to download base system RPMs from elsewhere than the Red Hat Content Delivery Network (CDN) official repositories, for example, a custom mirror in your network. Using official repository overrides disables the default repositories, and your custom mirror must contain all the necessary packages.
Custom third-party repositories
Use these to include packages that are not available in the official RHEL repositories.

3.1. Adding custom third-party repositories to RHEL image builder

You can add custom third-party sources to your repositories and manage these repositories by using the composer-cli.

Prerequisites

  • You have the URL of the custom third-party repository.

Procedure

  1. Create a repository source file, such as /root/repo.toml. For example:

    id = "k8s"
    name = "Kubernetes"
    type = "yum-baseurl"
    url = "https://server.example.com/repos/company_internal_packages/"
    check_gpg = false
    check_ssl = false
    system = false

    The type field accepts the following valid values: yum-baseurl, yum-mirrorlist, and yum-metalink.

  2. Save the file in the TOML format.
  3. Add the new third-party source to RHEL image builder:

    $ composer-cli sources add <file-name>.toml

Verification

  1. Check if the new source was successfully added:

    $ composer-cli sources list
  2. Check the new source content:

    $ composer-cli sources info <source_id>

3.2. Adding third-party repositories with specific distributions to RHEL image builder

You can specify a list of distributions in the custom third-party source file by using the optional field distro. The repository file uses the distribution string list while resolving dependencies during the image building.

Any request that specifies rhel-9 uses this source. For example, if you list packages and specify rhel-9, it includes this source. However, listing packages for the host distribution do not include this source.

Prerequisites

  • You have the URL of the custom third-party repository.
  • You have the list of distributions that you want to specify.

Procedure

  1. Create a repository source file, such as /root/repo.toml. For example, to specify the distribution:

    check_gpg = true
    check_ssl = true
    distros = ["rhel-9"]
    id = "rh9-local"
    name = "packages for RHEL"
    system = false
    type = "yum-baseurl"
    url = "https://local/repos/rhel9/projectrepo/"
  2. Save the file in the TOML format.
  3. Add the new third-party source to RHEL image builder:

    $ composer-cli sources add <file-name>.toml

Verification

  1. Check if the new source was successfully added:

    $ composer-cli sources list
  2. Check the new source content:

    $ composer-cli sources info <source_id>

3.3. Checking repositories metadata with GPG

To detect and avoid corrupted packages, you can use the DNF package manager to check the GNU Privacy Guard (GPG) signature on RPM packages, and also to check if the repository metadata has been signed with a GPG key.

You can either enter the gpgkey that you want to do the check over https by setting the gpgkeys field with the key URL. Alternatively, to improve security, you can also embed the whole key into the gpgkeys field, to import it directly instead of fetching the key from the URL.

Prerequisites

  • The directory that you want to use as a repository exists and contains packages.

Procedure

  1. Access the folder where you want to create a repository:

    $ cd repo/
  2. Run the createrepo_c to create a repository from RPM packages:

    $ createrepo_c .
  3. Access the directory where the repodata is:

    $ cd repodata/
  4. Sign your repomd.xml file:

    $ gpg -u <_gpg-key-email_> --yes --detach-sign --armor /srv/repo/example/repomd.xml
  5. To enable GPG signature checks in the repository:

    1. Set check_repogpg = true in the repository source.
    2. Enter the gpgkey that you want to do the check. If your key is available over https, set the gpgkeys field with the key URL for the key. You can add as many URL keys as you need.

      The following is an example:

      check_gpg = true
      check_ssl = true
      id = "signed local packages"
      name = "repository_name"
      type = "yum-baseurl"
      url = "https://local/repos/projectrepo/"
      check_repogpg = true
      gpgkeys=["https://local/keys/repokey.pub"]

      As an alternative, add the GPG key directly in the gpgkeys field, for example:

      check_gpg = true
      check_ssl = true
      check_repogpg
      id = "custom-local"
      name = "signed local packages"
      type = "yum-baseurl"
      url = "https://local/repos/projectrepo/"
      gpgkeys=["https://remote/keys/other-repokey.pub",
      '''-----BEGIN PGP PUBLIC KEY BLOCK-----
      …​
      -----END PGP PUBLIC KEY BLOCK-----''']
      • If the test does not find the signature, the GPG tool shows an error similar to the following one:

        $ GPG verification is enabled, but GPG signature is not available.
        This may be an error or the repository does not support GPG verification:
        Status code: 404 for http://repo-server/rhel/repodata/repomd.xml.asc (IP: 192.168.1.3)
      • If the signature is invalid, the GPG tool shows an error similar to the following one:

        repomd.xml GPG signature verification error: Bad GPG signature

Verification

  • Test the signature of the repository manually:

    $ gpg --verify /srv/repo/example/repomd.xml.asc

3.4. RHEL image builder official repository overrides

RHEL image builder osbuild-composer back end does not inherit the system repositories located in the /etc/yum.repos.d/ directory. Instead, it has its own set of official repositories defined in the /usr/share/osbuild-composer/repositories directory. This includes the Red Hat official repository, which contains the base system RPMs to install additional software or update already installed programs to newer versions. If you want to override the official repositories, you must define overrides in /etc/osbuild-composer/repositories/. This directory is for user defined overrides and the files located there take precedence over those in the /usr/share/osbuild-composer/repositories/ directory.

The configuration files are not in the usual DNF repository format known from the files in /etc/yum.repos.d/. Instead, they are JSON files.

3.5. Overriding a system repository

You can configure your own repository override for RHEL image builder in the /etc/osbuild-composer/repositories directory.

Prerequisites

  • You have a custom repository that is accessible from your host system.

Procedure

  1. Create the /etc/osbuild-composer/repositories/ directory to store your repository overrides:

    $ sudo mkdir -p /etc/osbuild-composer/repositories
  2. Create a JSON file, using a name corresponding to your RHEL version. Alternatively, you can copy the file for your distribution from /usr/share/osbuild-composer/ and modify its content.

    For RHEL 9.3, use /etc/osbuild-composer/repositories/rhel-93.json.

  3. Add the following structure to your JSON file. Specify only one of the following attributes, in the string format:

    • baseurl - The base URL of the repository.
    • metalink - The URL of a metalink file that contains a list of valid mirror repositories.
    • mirrorlist - The URL of a mirrorlist file that contains a list of valid mirror repositories. The remaining fields, such as gpgkey, and metadata_expire, are optional.

      For example:

      {
           "x86_64": [
              {
                  "name": "baseos",
                  "baseurl": "http://mirror.example.com/composes/released/RHEL-9/9.0/BaseOS/x86_64/os/",
                  "gpgkey": "-----BEGIN PGP PUBLIC KEY BLOCK-----\n\n (…​)",
                  "check_gpg": true
              }
          ]
      }

      Alternatively, you can copy the JSON file for your distribution, by replacing rhel-version.json with your RHEL version, for example: rhel-9.json.

      $  cp /usr/share/osbuild-composer/repositories/rhel-version.json /etc/osbuild-composer/repositories/
  4. Optional: Verify the JSON file:

    $ json_verify  /etc/osbuild-composer/repositories/<file>.json
  5. Edit the baseurl paths in the rhel-9.json file and save it. For example:

    $ /etc/osbuild-composer/repositories/rhel-version.json
  6. Restart the osbuild-composer.service:

    $ sudo systemctl restart osbuild-composer.service

Verification

  • Check if the repository points to the correct URLs:

    $ cat /etc/yum.repos.d/redhat.repo

    You can see that the repository points to the correct URLs which are copied from the /etc/yum.repos.d/redhat.repo file.

3.6. Overriding a system repository that requires subscriptions

You can set up the osbuild-composer service to use system subscriptions that are defined in the /etc/yum.repos.d/redhat.repo file. To use a system subscription in osbuild-composer, define a repository override that has the following details:

  • The same baseurl as the repository defined in /etc/yum.repos.d/redhat.repo.
  • The value of ”rhsm”: true defined in the JSON object.

    Note

    osbuild-composer does not automatically use repositories defined in /etc/yum.repos.d/. You need to manually specify them either as a system repository override or as an additional source by using composer-cli. The “BaseOS” and “AppStream” repositories usually use system repository overrides, whereas all the other repositories use composer-cli sources.

Prerequisites

Procedure

  1. Get the baseurl from the /etc/yum.repos.d/redhat.repo file:

    # cat /etc/yum.repos.d/redhat.repo
    [AppStream]
    name = AppStream mirror example
    baseurl = https://mirror.example.com/RHEL-9/9.0/AppStream/x86_64/os/
    enabled = 1
    gpgcheck = 0
    sslverify = 1
    sslcacert = /etc/pki/ca1/ca.crt
    sslclientkey = /etc/pki/ca1/client.key
    sslclientcert = /etc/pki/ca1/client.crt
    metadata_expire = 86400
    enabled_metadata = 0
  2. Configure the repository override to use the same baseurl and set rhsm to true:

    {
        "x86_64": [
            {
                "name": "AppStream mirror example",
                "baseurl": "https://mirror.example.com/RHEL-9/9.0/AppStream/x86_64/os/",
                "gpgkey": "-----BEGIN PGP PUBLIC KEY BLOCK-----\n\n (…​)",
                "check_gpg": true,
                "rhsm": true
            }
        ]
    }
  3. Restart the osbuild-composer.service:

    $ sudo systemctl restart osbuild-composer.service

Chapter 4. Creating system images by using RHEL image builder CLI

RHEL image builder is a tool for creating custom system images. To control RHEL image builder and create your custom system images, you can use the command-line interface (CLI) or the web console interface.

Important

The RHEL image builder tool does not support building RHEL 9 images on a RHEL 8 system. You can only build an image from the earlier version of the image you use in the host distribution.

4.1. Introducing the RHEL image builder command-line interface

You can use the RHEL image builder command-line interface (CLI) to create blueprints, by running the composer-cli command with the suitable options and subcommands.

The workflow for the command-line interface can be summarized as follows:

  1. Create a blueprint or export (save) an existing blueprint definition to a plain text file
  2. Edit this file in a text editor
  3. Import the blueprint text file back into image builder
  4. Run a compose to build an image from the blueprint
  5. Export the image file to download it

Apart from the basic subcommands to create a blueprint, the composer-cli command offers many subcommands to examine the state of configured blueprints and composes.

4.2. Using RHEL image builder as a non-root user

To run the composer-cli commands as non-root, the user must be in the weldr group.

Prerequisites

  • You have created a user

Procedure

  • To add a user to the weldr or root groups, run the following commands:

    $ sudo usermod -a -G weldr user
    $ newgrp weldr

4.3. Creating a blueprint by using the command-line interface

You can create a new RHEL image builder blueprint using the command-line interface (CLI). The blueprint describes the final image and its customizations, such as packages, and kernel customizations.

Prerequisite

  • You are logged in as the root user or a user who is a member of the welder group

Procedure

  1. Create a plain text file with the following contents:

    name = "BLUEPRINT-NAME"
    description = "LONG FORM DESCRIPTION TEXT"
    version = "0.0.1"
    modules = []
    groups = []

    Replace BLUEPRINT-NAME and LONG FORM DESCRIPTION TEXT with a name and description for your blueprint.

    Replace 0.0.1 with a version number according to the Semantic Versioning scheme.

  2. For every package that you want to be included in the blueprint, add the following lines to the file:

    [[packages]]
    name = "package-name"
    version = "package-version"

    Replace package-name with the name of the package, such as httpd, gdb-doc, or coreutils.

    Optionally, replace package-version with the version to use. This field supports dnf version specifications:

    • For a specific version, use the exact version number such as 8.7.0.
    • For the latest available version, use the asterisk *.
    • For the latest minor version, use formats such as 8.*.
  3. Customize your blueprints to suit your needs. For example, disable Simultaneous Multi Threading (SMT), add the following lines to the blueprint file:

    [customizations.kernel]
    append = "nosmt=force"

    For additional customizations available, see Supported Image Customizations.

  4. Save the file, for example, as BLUEPRINT-NAME.toml and close the text editor.
  5. Push the blueprint:

    # composer-cli blueprints push BLUEPRINT-NAME.toml

    Replace BLUEPRINT-NAME with the value you used in previous steps.

    Note

    To create images using composer-cli as non-root, add your user to the weldr or root groups.

    # usermod -a -G weldr user
    $ newgrp weldr

Verification

  • List the existing blueprints to verify that the blueprint has been pushed and exists:

    # composer-cli blueprints list
  • Display the blueprint configuration you have just added:

    # composer-cli blueprints show BLUEPRINT-NAME
  • Check whether the components and versions listed in the blueprint and their dependencies are valid:

    # composer-cli blueprints depsolve BLUEPRINT-NAME

    If RHEL image builder is unable to solve the dependencies of a package from your custom repositories, remove the osbuild-composer cache:

    $ sudo rm -rf /var/cache/osbuild-composer/*
    $ sudo systemctl restart osbuild-composer

4.4. Editing a blueprint with command-line interface

You can edit an existing blueprint in the command-line (CLI) interface to, for example, add a new package, or define a new group, and to create your customized images. For that, follow the steps:

Prerequisites

  • You have created a blueprint

Procedure

  1. List the existing blueprints:

    # composer-cli blueprints list
  2. Save the blueprint to a local text file:

    # composer-cli blueprints save BLUEPRINT-NAME
  3. Edit the BLUEPRINT-NAME.toml file with a text editor and make your changes.
  4. Before finishing the edits, verify that the file is a valid blueprint:

    1. Remove the following line from the blueprint, if present:

      packages = []
    2. Increase the version number, for example, from 0.0.1 to 0.1.0. Remember that RHEL image builder blueprint versions must use the Semantic Versioning scheme. Note also that if you do not change the version, the patch version component increases automatically.
  5. Save the file and close the text editor.
  6. Push the blueprint back into RHEL image builder:

    # composer-cli blueprints push BLUEPRINT-NAME.toml
    Note

    To import the blueprint back into RHEL image builder, supply the file name including the .toml extension, while in other commands use only the blueprint name.

Verification

  1. To verify that the contents uploaded to RHEL image builder match your edits, list the contents of blueprint:

    # composer-cli blueprints show BLUEPRINT-NAME
  2. Check whether the components and versions listed in the blueprint and their dependencies are valid:

    # composer-cli blueprints depsolve BLUEPRINT-NAME

Additional resources

4.5. Creating a system image with RHEL image builder in the command-line interface

You can build a customized RHEL image by using the RHEL image builder command-line interface. For that, you must specify a blueprint and an image type. Optionally, you can also specify a distribution. If you do not specify a distribution, it will use the same distribution and version as the host system. The architecture is also the same as the one on the host.

Prerequisites

Procedure

  1. Optional: List the image formats you can create:

    # composer-cli compose types
  2. Start the compose:

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

    Replace BLUEPRINT-NAME with the name of the blueprint, and IMAGE-TYPE with the type of the image. For the available values, see the output of the composer-cli compose types command.

    The compose process starts in the background and shows the composer Universally Unique Identifier (UUID).

  3. The image creation can take up to ten minutes to complete.

    To check the status of the compose:

    # composer-cli compose status

    A finished compose shows the FINISHED status value. To identify your compose in the list, use its UUID.

  4. After the compose process is finished, download the resulting image file:

    # composer-cli compose image UUID

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

Verification

After you create your image, you can check the image creation progress using the following commands:

  • Download the metadata of the image to get a .tar file of the metadata for the compose:

    $ sudo composer-cli compose metadata UUID
  • Download the logs of the image:

    $ sudo composer-cli compose logs UUID

    The command creates a .tar file that contains the logs for the image creation. If the logs are empty, you can check the journal.

  • Check the journal:

    $ journalctl | grep osbuild
  • Check the manifest of the image:

    $ sudo cat /var/lib/osbuild-composer/jobs/job_UUID.json

    You can find the job_UUID.json in the journal.

Additional resources

4.6. Basic RHEL image builder command-line commands

The RHEL image builder command-line interface offers the following subcommands.

Blueprint manipulation

List all available blueprints
# composer-cli blueprints list
Show a blueprint contents in the TOML format
# composer-cli blueprints show <BLUEPRINT-NAME>
Save (export) blueprint contents in the TOML format into a file BLUEPRINT-NAME.toml
# composer-cli blueprints save <BLUEPRINT-NAME>
Remove a blueprint
# composer-cli blueprints delete <BLUEPRINT-NAME>
Push (import) a blueprint file in the TOML format into RHEL image builder
# composer-cli blueprints push <BLUEPRINT-NAME>

Composing images from blueprints

List the available image types
# composer-cli compose types
Start a compose
# composer-cli compose start <BLUEPRINT> <COMPOSE-TYPE>
List all composes
# composer-cli compose list
List all composes and their status
# composer-cli compose status
Cancel a running compose
# composer-cli compose cancel <COMPOSE-UUID>
Delete a finished compose
# composer-cli compose delete <COMPOSE-UUID>
Show detailed information about a compose
# composer-cli compose info <COMPOSE-UUID>
Download image file of a compose
# composer-cli compose image <COMPOSE-UUID>
See more subcommands and options
# composer-cli help

Additional resources

  • composer-cli(1) man page

4.7. RHEL image builder blueprint format

RHEL image builder blueprints are presented to the user as plain text in the TOML format.

The elements of a typical blueprint file include the following:

The blueprint metadata
name = "<BLUEPRINT-NAME>"
description = "<LONG FORM DESCRIPTION TEXT>"
version = "<VERSION>"

The BLUEPRINT-NAME and LONG FORM DESCRIPTION TEXT field are a name and description for your blueprint.

The VERSION is a version number according to the Semantic Versioning scheme, and is present only once for the entire blueprint file.

Groups to include in the image
[[groups]]
name = "group-name"

The group entry describes a group of packages to be installed into the image. Groups use the following package categories:

  • Mandatory
  • Default
  • Optional

    The group-name is the name of the group, for example, anaconda-tools, widget, wheel or users. Blueprints install the mandatory and default packages. There is no mechanism for selecting optional packages.

Packages to include in the image
[[packages]]
name = "<package-name>"
version = "<package-version>"

package-name is the name of the package, such as httpd, gdb-doc, or coreutils.

package-version is a version to use. This field supports dnf version specifications:

  • For a specific version, use the exact version number such as 8.7.0.
  • For latest available version, use the asterisk *.
  • For a latest minor version, use a format such as 8.*.

Repeat this block for every package to include.

Note

There are no differences between packages and modules in the RHEL image builder tool. Both are treated as RPM package dependencies.

4.8. Supported image customizations

You can customize your image by adding customizations to your blueprint, such as:

  • Adding an additional RPM package
  • Enabling a service
  • Customizing a kernel command line parameter.

Between others. You can use several image customizations within blueprints. By using the customizations, you can add packages and groups to the image that are not available in the default packages. To use these options, configure the customizations in the blueprint and import (push) it to RHEL image builder.

4.8.1. Selecting a distribution

You can use the distro field to select the distribution to use when composing your images, or depsolving the blueprint. If distro is left blank it will use the host distribution. If you do not specify a distribution, the blueprint uses the host distribution. In case you upgrade the host operating system, the blueprints with no distribution set build images using the new operating system version. You cannot build an operating system image that differs from the RHEL image builder host.

Procedure

  • Customize the blueprint with the distro to always build the specified RHEL image:

    name = "blueprint_name"
    description = "blueprint_version"
    version = "0.1"
    distro = "different_minor_version"

Replace "different_minor_version" to build a different minor version, for example, if you want to build a RHEL 9.3 image, use distro = "rhel-93". On RHEL 9.3 image, you can build minor versions such as RHEL 9.2, RHEL 8.9 and earlier releases.

4.8.2. Selecting a package group

Customize the blueprint with packages and modules. The name attribute is a required string. The version attribute is an optional string that, if not provided, uses the latest version in the repositories.

Note

Currently, there are no differences between packages and modules in osbuild-composer. Both are treated as an RPM package dependency.

Procedure

  • Customize your blueprint with a package:

    [[packages]]
    name = "package_group_name"

    Replace "package_group_name" with the name of the group. For example, "tmux".

    [[packages]]
    name = "tmux"
    version = "2.9a"

4.8.3. Setting the image hostname

The customizations.hostname is an optional string that you can use to configure the final image hostname. This customization is optional, and if you do not set it, the blueprint uses the default hostname.

Procedure

  • Customize the blueprint to configure the hostname:

    [customizations]
    hostname = "baseimage"

4.8.4. Specifying additional users

Add a user to the image, and optionally, set their SSH key. All fields for this section are optional except for the name.

Procedure

  • Customize the blueprint to add a user to the image:

    [[customizations.user]]
    name = "USER-NAME"
    description = "USER-DESCRIPTION"
    password = "PASSWORD-HASH"
    key = "PUBLIC-SSH-KEY"
    home = "/home/USER-NAME/"
    shell = "/usr/bin/bash"
    groups = ["users", "wheel"]
    uid = NUMBER
    gid = NUMBER

    The GID is optional and must already exist in the image. Optionally, a package creates it, or the blueprint creates the GID by using the [[customizations.group]] entry.

    Replace PASSWORD-HASH with the actual password hash. To generate the password hash, use a command such as:

    $ python3 -c 'import crypt,getpass;pw=getpass.getpass();print(crypt.crypt(pw) if (pw==getpass.getpass("Confirm: ")) else exit())'

    Replace the other placeholders with suitable values.

    Enter the name value and omit any lines you do not need.

    Repeat this block for every user to include.

4.8.5. Specifying additional groups

Specify a group for the resulting system image. Both the name and the gid attributes are mandatory.

Procedure

  • Customize the blueprint with a group:

    [[customizations.group]]
    name = "GROUP-NAME"
    gid = NUMBER

    Repeat this block for every group to include.

4.8.6. Setting SSH key for existing users

You can use customizations.sshkey to set an SSH key for the existing users in the final image. Both user and key attributes are mandatory.

Procedure

  • Customize the blueprint by setting an SSH key for existing users:
[[customizations.sshkey]]
user = "root"
key = "PUBLIC-SSH-KEY"
Note

You can only configure the customizations.sshkey customization for existing users. To create a user and set an SSH key, see the User specifications for the resulting system image customization.

4.8.7. Appending a kernel argument

You can append arguments to the boot loader kernel command line. By default, RHEL image builder builds a default kernel into the image. However, you can customize the kernel by configuring it in the blueprint.

Procedure

  • Append a kernel boot parameter option to the defaults:

    [customizations.kernel]
    append = "KERNEL-OPTION"
  • Define a kernel name to use in an image

    [customizations.kernel]
    name = "KERNEL-rt"

4.8.8. Setting time zone and NTP

You can customize your blueprint to configure the time zone and the Network Time Protocol (NTP). Both timezone and ntpservers attributes are optional strings. If you do not customize the time zone, the system uses Universal Time, Coordinated (UTC). If you do not set NTP servers, the system uses the default distribution.

Procedure

  • Customize the blueprint with the timezone and the ntpservers you want:

    [customizations.timezone]
    timezone = "TIMEZONE"
    ntpservers = "NTP_SERVER"

    For example:

    [customizations.timezone]
    timezone = "US/Eastern"
    ntpservers = ["0.north-america.pool.ntp.org", "1.north-america.pool.ntp.org"]
    Note

    Some image types, such as Google Cloud, already have NTP servers set up. You cannot override it because the image requires the NTP servers to boot in the selected environment. However, you can customize the time zone in the blueprint.

4.8.9. Customizing the locale settings

You can customize the locale settings for your resulting system image. Both language and the keyboard attributes are mandatory. You can add many other languages. The first language you add is the primary language and the other languages are secondary.

Procedure

  • Set the locale settings:
[customizations.locale]
languages = ["LANGUAGE"]
keyboard = "KEYBOARD"

For example:

[customizations.locale]
languages = ["en_US.UTF-8"]
keyboard = "us"
  • To list the values supported by the languages, run the following command:

    $ localectl list-locales
  • To list the values supported by the keyboard, run the following command:

    $ localectl list-keymaps

4.8.10. Customizing firewall

Set the firewall for the resulting system image. By default, the firewall blocks incoming connections, except for services that enable their ports explicitly, such as sshd.

If you do not want to use the [customizations.firewall] or the [customizations.firewall.services], either remove the attributes, or set them to an empty list []. If you only want to use the default firewall setup, you can omit the customization from the blueprint.

Note

The Google and OpenStack templates explicitly disable the firewall for their environment. You cannot override this behavior by setting the blueprint.

Procedure

  • Customize the blueprint with the following settings to open other ports and services:

    [customizations.firewall]
    ports = ["PORTS"]

    Where ports is an optional list of strings that contain ports or a range of ports and protocols to open. You can configure the ports by using the following format: port:protocol format. You can configure the port ranges by using the portA-portB:protocol format. For example:

    [customizations.firewall]
    ports = ["22:tcp", "80:tcp", "imap:tcp", "53:tcp", "53:udp", "30000-32767:tcp", "30000-32767:udp"]

    You can use numeric ports, or their names from the /etc/services to enable or disable port lists.

  • Specify which firewall services to enable or disable in the customizations.firewall.service section:

    [customizations.firewall.services]
    enabled = ["SERVICES"]
    disabled = ["SERVICES"]
  • You can check the available firewall services:

    $ firewall-cmd --get-services

    For example:

    [customizations.firewall.services]
    enabled = ["ftp", "ntp", "dhcp"]
    disabled = ["telnet"]
    Note

    The services listed in firewall.services are different from the service-names available in the /etc/services file.

4.8.11. Enabling or disabling services

You can control which services to enable during the boot time. Some image types already have services enabled or disabled to ensure that the image works correctly and you cannot override this setup. The [customizations.services] settings in the blueprint do not replace these services, but add the services to the list of services already present in the image templates.

Procedure

  • Customize which services to enable during the boot time:

    [customizations.services]
    enabled = ["SERVICES"]
    disabled = ["SERVICES"]

    For example:

    [customizations.services]
    enabled = ["sshd", "cockpit.socket", "httpd"]
    disabled = ["postfix", "telnetd"]

4.8.12. Specifying a custom filesystem configuration

You can specify a custom filesystem configuration in your blueprints and therefore create images with a specific disk layout, instead of the default layout configuration. By using the non-default layout configuration in your blueprints, you can benefit from:

  • Security benchmark compliance
  • Protection against out-of-disk errors
  • Improved performance
  • Consistency with existing setups
Note

The filesystem customization is not supported for OSTree systems, because OSTree images have their own mount rule, such as read-only.

The blueprint supports the following mountpoints and their sub-directories:

  • / - the root mount point
  • /var
  • /home
  • /opt
  • /srv
  • /usr
  • /app
  • /data
  • /boot - The blueprint supports the /boot customization from RHEL 8.7 and RHEL 9.1 onward.
Note

Customizing mount points is only supported from RHEL 9.0 distributions onward, by using the CLI. In earlier distributions, you can only specify the root partition as a mount point and specify the size argument as an alias for the image size.

If you have more than one partition in the customized image, you can create images with a customized file system partition on LVM and resize those partitions at runtime. To do this, you can specify a customized filesystem configuration in your blueprint and therefore create images with the required disk layout. The default filesystem layout remains unchanged - if you use plain images without file system customization, and cloud-init resizes the root partition.

The blueprint automatically converts the file system customization to an LVM partition.

You can use the custom file blueprint customization to create new files or to replace existing files. The parent directory of the file you specify must exist, otherwise, the image build fails. Ensure that the parent directory exists by specifying it in the [[customizations.directories]] customization.

Warning

If you combine the files customizations with other blueprint customizations, it might affect the functioning of the other customizations, or it might override the current files customizations.

With the [[customizations.files]] blueprint customization you can:

  • Create new text files.
  • Modifying existing files. WARNING: this can override the existing content.
  • Set user and group ownership for the file you are creating.
  • Set the mode permission in the octal format.

You cannot create or replace the following files:

  • /etc/fstab
  • /etc/shadow
  • /etc/passwd
  • /etc/group

You can create customized files and directories in your image, by using the [[customizations.files]] and the [[customizations.directories]] blueprint customizations. You can use these customizations only in the /etc directory.

Note

These blueprint customizations are supported by all image types, except the image types that deploy OSTree commits, such as edge-raw-image, edge-installer, and edge-simplified-installer.

Warning

If you use the customizations.directories with a directory path which already exists in the image with mode, user or group already set, the image build fails to prevent changing the ownership or permissions of the existing directory.

With the [[customizations.directories]] blueprint customization you can:

  • Create new directories.
  • Set user and group ownership for the directory you are creating.
  • Set the directory mode permission in the octal format.
  • Ensure that parent directories are created as needed.

With the [[customizations.files]] blueprint customization you can:

  • Create new text files.
  • Modifying existing files. WARNING: this can override the existing content.
  • Set user and group ownership for the file you are creating.
  • Set the mode permission in the octal format.
Note

You cannot create or replace the following files:

  • /etc/fstab
  • /etc/shadow
  • /etc/passwd
  • /etc/group

Procedure

  • Customize the filesystem configuration in your blueprint:

    [[customizations.filesystem]]
    mountpoint = "MOUNTPOINT"
    size = MINIMUM-PARTITION-SIZE

    The MINIMUM-PARTITION-SIZE value has no default size format. The blueprint customization supports the following values and units: kB to TB and KiB to TiB. For example, you can define the mount point size in bytes:

    [[customizations.filesystem]]
    mountpoint = "/var"
    size = 1073741824
  • Define the mount point size by using units. For example:

    [[customizations.filesystem]]
    mountpoint = "/opt"
    size = "20 GiB"
    [[customizations.filesystem]]
    mountpoint = "/boot"
    size = "1 GiB"
  • Create customized directories under the /etc directory for your image by using [[customizations.directories]]:

    [[customizations.directories]]
    path = "/etc/directory_name"
    mode = "octal_access_permission"
    user = "user_string_or_integer"
    group = "group_string_or_integer"
    ensure_parents = boolean

    The blueprint entries are described as following:

  • path - Mandatory - enter the path to the directory that you want to create. It must be an absolute path under the /etc directory.
  • mode - Optional - set the access permission on the directory, in the octal format. If you do not specify a permission, it defaults to 0755. The leading zero is optional.
  • user - Optional - set a user as the owner of the directory. If you do not specify a user, it defaults to root. You can specify the user as a string or as an integer.
  • group - Optional - set a group as the owner of the directory. If you do not specify a group, it defaults to root. You can specify the group as a string or as an integer.
  • ensure_parents - Optional - Specify whether you want to create parent directories as needed. If you do not specify a value, it defaults to false.
  • Create customized file under the /etc directory for your image by using [[customizations.directories]]:

    [[customizations.files]]
    path = "/etc/directory_name"
    mode = "octal_access_permission"
    user = "user_string_or_integer"
    group = "group_string_or_integer"
    data = "Hello world!"

    The blueprint entries are described as following:

  • path - Mandatory - enter the path to the file that you want to create. It must be an absolute path under the /etc directory.
  • mode Optional - set the access permission on the file, in the octal format. If you do not specify a permission, it defaults to 0644. The leading zero is optional.
  • user - Optional - set a user as the owner of the file. If you do not specify a user, it defaults to root. You can specify the user as a string or as an integer.
  • group - Optional - set a group as the owner of the file. If you do not specify a group, it defaults to root. You can specify the group as a string or as an integer.
  • data - Optional - Specify the content of a plain text file. If you do not specify a content, it creates an empty file.

4.9. Packages installed by RHEL image builder

When you create a system image using RHEL image builder, the system installs a set of base package groups.

Note

When you add additional components to your blueprint, ensure that the packages in the components you added do not conflict with any other package components. Otherwise, the system fails to solve dependencies and creating your customized image fails. You can check if there is no conflict between the packages by running the command:

# composer-cli blueprints depsolve BLUEPRINT-NAME

Table 4.1. Default packages to support image type creation

Image typeDefault Packages

ami

checkpolicy, chrony, cloud-init, cloud-utils-growpart, @Core, dhcp-client, gdisk, insights-client, kernel, langpacks-en, net-tools, NetworkManager, redhat-release, redhat-release-eula, rng-tools, rsync, selinux-policy-targeted, tar, yum-utils

openstack

@core, langpacks-en

qcow2

@core, chrony, dnf, kernel, dnf, nfs-utils, dnf-utils, cloud-init, python3-jsonschema, qemu-guest-agent, cloud-utils-growpart, dracut-norescue, tar, tcpdump, rsync, dnf-plugin-spacewalk, rhn-client-tools, rhnlib, rhnsd, rhn-setup, NetworkManager, dhcp-client, cockpit-ws, cockpit-system, subscription-manager-cockpit, redhat-release, redhat-release-eula, rng-tools, insights-client

tar

policycoreutils, selinux-policy-targeted

vhd

@core, langpacks-en

vmdk

@core, chrony, cloud-init, firewalld, langpacks-en, open-vm-tools, selinux-policy-targeted

edge-commit

attr, audit, basesystem, bash, bash-completion, chrony, clevis, clevis-dracut, clevis-luks, container-selinux, coreutils,criu, cryptsetup, curl, dnsmasq, dosfstools, dracut-config-generic, dracut-network, e2fsprogs, firewalld, fuse-overlayfs, fwupd, glibc, glibc-minimal-langpack, gnupg2, greenboot, gzip, hostname, ima-evm-utils, iproute, iptables, iputils, keyutils, less, lvm2, NetworkManager, NetworkManager-wifi, NetworkManager-wwan, nss-altfiles, openssh-clients, openssh-server, passwd, pinentry, platform-python, podman, policycoreutils, policycoreutils-python-utils, polkit, procps-ng, redhat-release, rootfiles, rpm, rpm-ostree, rsync, selinux-policy-targeted, setools-console, setup, shadow-utils, shadow-utils, skopeo, slirp4netns, sudo, systemd, tar, tmux, traceroute, usbguard, util-linux, vim-minimal, wpa_supplicant, xz

edge-container

dnf, dosfstools, e2fsprogs, glibc, lorax-templates-generic, lorax-templates-rhel, lvm2, policycoreutils, python36, python3-iniparse, qemu-img, selinux-policy-targeted, systemd, tar, xfsprogs, xz

edge-installer

aajohan-comfortaa-fonts, abattis-cantarell-fonts, alsa-firmware, alsa-tools-firmware, anaconda, anaconda-install-env-deps, anaconda-widgets, audit, bind-utils, bitmap-fangsongti-fonts, bzip2, cryptsetup, dbus-x11, dejavu-sans-fonts, dejavu-sans-mono-fonts, device-mapper-persistent-data, dnf, dump, ethtool, fcoe-utils, ftp, gdb-gdbserver, gdisk, gfs2-utils, glibc-all-langpacks, google-noto-sans-cjk-ttc-fonts, gsettings-desktop-schemas, hdparm, hexedit, initscripts, ipmitool, iwl3945-firmware, iwl4965-firmware, iwl6000g2a-firmware, iwl6000g2b-firmware, jomolhari-fonts, kacst-farsi-fonts, kacst-qurn-fonts, kbd, kbd-misc, kdump-anaconda-addon, khmeros-base-fonts, libblockdev-lvm-dbus, libertas-sd8686-firmware, libertas-sd8787-firmware, libertas-usb8388-firmware, libertas-usb8388-olpc-firmware, libibverbs, libreport-plugin-bugzilla, libreport-plugin-reportuploader, libreport-rhel-anaconda-bugzilla, librsvg2, linux-firmware, lklug-fonts, lldpad, lohit-assamese-fonts, lohit-bengali-fonts, lohit-devanagari-fonts, lohit-gujarati-fonts, lohit-gurmukhi-fonts, lohit-kannada-fonts, lohit-odia-fonts, lohit-tamil-fonts, lohit-telugu-fonts, lsof, madan-fonts, metacity, mtr, mt-st, net-tools, nmap-ncat, nm-connection-editor, nss-tools, openssh-server, oscap-anaconda-addon, pciutils, perl-interpreter, pigz, python3-pyatspi, rdma-core, redhat-release-eula, rpm-ostree, rsync, rsyslog, sg3_utils, sil-abyssinica-fonts, sil-padauk-fonts, sil-scheherazade-fonts, smartmontools, smc-meera-fonts, spice-vdagent, strace, system-storage-manager, thai-scalable-waree-fonts, tigervnc-server-minimal, tigervnc-server-module, udisks2, udisks2-iscsi, usbutils, vim-minimal, volume_key, wget, xfsdump, xorg-x11-drivers,xorg-x11-fonts-misc,xorg-x11-server-utils,xorg-x11-server-Xorg, xorg-x11-xauth

edge-simplified-installer

attr, basesystem, binutils, bsdtar, clevis-dracut, clevis-luks, cloud-utils-growpart, coreos-installer, coreos-installer-dracut, coreutils, device-mapper-multipath, dnsmasq, dosfstools, dracut-live, e2fsprogs, fcoe-utils, fdo-init, gzip, ima-evm-utils, iproute, iptables, iputils, iscsi-initiator-utils, keyutils, lldpad, lvm2, passwd, policycoreutils, policycoreutils-python-utils, procps-ng, rootfiles, setools-console, sudo, traceroute, util-linux

image-installer

anaconda-dracut, curl, dracut-config-generic, dracut-network, hostname, iwl100-firmware, iwl1000-firmware, iwl105-firmware, iwl135-firmware, iwl2000-firmware, iwl2030-firmware, iwl3160-firmware, iwl5000-firmware, iwl5150-firmware, iwl6000-firmware, iwl6050-firmware, iwl7260-firmware, kernel, less, nfs-utils, openssh-clients, ostree, plymouth, prefixdevname, rng-tools, rpcbind, selinux-policy-targeted, systemd, tar, xfsprogs, xz

edge-raw-image

dnf, dosfstools, e2fsprogs, glibc, lorax-templates-generic, lorax-templates-rhel, lvm2, policycoreutils, python36, python3-iniparse, qemu-img, selinux-policy-targeted, systemd, tar, xfsprogs, xz

gce

@core, langpacks-en, acpid, dhcp-client, dnf-automatic, net-tools, python3, rng-tools, tar, vim

Additional resources

4.10. Enabled services on custom images

When you use image builder to configure a custom image, the default services that the image uses are determined by the following:

  • The RHEL release on which you use the osbuild-composer utility
  • The image type

For example, the ami image type enables the sshd, chronyd, and cloud-init services by default. If these services are not enabled, the custom image does not boot.

Table 4.2. Enabled services to support image type creation

Image typeDefault enabled Services

ami

sshd, cloud-init, cloud-init-local, cloud-config, cloud-final

openstack

sshd, cloud-init, cloud-init-local, cloud-config, cloud-final

qcow2

cloud-init

rhel-edge-commit

No extra service enables by default

tar

No extra service enables by default

vhd

sshd, chronyd, waagent, cloud-init, cloud-init-local, cloud-config, cloud-final

vmdk

sshd, chronyd, vmtoolsd, cloud-init

Note: You can customize which services to enable during the system boot. However, the customization does not override services enabled by default for the mentioned image types.

Additional resources

Chapter 5. Creating system images by using RHEL image builder web console interface

RHEL image builder is a tool for creating custom system images. To control RHEL image builder and create your custom system images, you can use the web console interface. Note that the command-line interface is the currently preferred alternative, because it offers more features.

5.1. Accessing the RHEL image builder dashboard in the RHEL web console

With the cockpit-composer plugin for the RHEL web console, you can manage image builder blueprints and composes using a graphical interface.

Prerequisites

  • You must have root access to the system.
  • You installed RHEL image builder.
  • You installed the cockpit-composer package.

Procedure

  1. On the host, open https://<_localhost_>:9090/ in a web browser.
  2. Log in to the web console as the root user.
  3. To display the RHEL image builder controls, click the Image Builder button, in the upper-left corner of the window.

    The RHEL image builder dashboard opens, listing existing blueprints, if any.

5.2. Creating a blueprint in the web console interface

Creating a blueprint is a necessary step before creating the customized RHEL system image. All the customizations are optional.

Note

These blueprint customizations are available for Red Hat Enterprise Linux 9.2 or later versions and Red Hat Enterprise Linux 8.8 or later versions.

Prerequisites

Procedure

  1. Click Create Blueprint in the upper-right corner.

    A dialog wizard with fields for the blueprint name and description opens.

  2. On the Details page:

    1. Enter the name of the blueprint and, optionally, its description.
    2. Click Next.
  3. Optional: In the Packages page:

    1. On the Available packages search, enter the package name
    2. Click the > button to move it to the Chosen packages field.
    3. Repeat the previous steps to search and include as many packages as you want.
    4. Click Next.

      Note

      These customizations are all optional unless otherwise specified.

  4. On the Kernel page, enter a kernel name and the command-line arguments.
  5. On the File system page, you can select Use automatic partitioning or Manually configure partitions for your image file system. For manually configuring the partitions, complete the following steps:

    1. Click the Manually configure partitions button.

      The Configure partitions section opens, showing the configuration based on Red Hat standards and security guides.

    2. From the dropdown menu, provide details to configure the partitions:

      1. For the Mount point field, select one of the following mount point type options:

        • / - the root mount point
        • /var
        • /home
        • /opt
        • /srv
        • /usr
        • /app
        • /data
        • /tmp
        • /usr/local

          You can also add an additional path to the Mount point, such as /tmp. For example: /var as a prefix and /tmp as an additional path results in /var/tmp.

          Note

          Depending on the Mount point type you choose, the file system type changes to xfs.

      2. For the Minimum size partition field of the file system, enter the needed minimum partition size. In the Minimum size dropdown menu, you can use common size units such as GiB, MiB, or KiB. The default unit is GiB.

        Note

        Minimum size means that RHEL image builder can still increase the partition sizes, in case they are too small to create a working image.

    3. To add more partitions, click the Add partition button. If you see the following error message: Duplicate partitions: Only one partition at each mount point can be created., you can:

      1. Click the Remove button to remove the duplicated partition.
      2. Choose a new mount point for the partition you want to create.
    4. After you finish the partitioning configuration, click Next.
  6. On the Services page, you can enable or disable services:

    1. Enter the service names you want to enable or disable, separating them by a comma, by space, or by pressing the Enter key. Click Next.
  7. On the Firewall page, set up your firewall setting:

    1. Enter the Ports, and the firewall services you want to enable or disable.
    2. Click the Add zone button to manage your firewall rules for each zone independently. Click Next.
  8. On the Users page, add a users by following the steps:

    1. Click Add user.
    2. Enter a Username, a password, and a SSH key. You can also mark the user as a privileged user, by clicking the Server administrator checkbox. Click Next.
  9. On the Groups page, add groups by completing the following steps:

    1. Click the Add groups button:

      1. Enter a Group name and a Group ID. You can add more groups. Click Next.
  10. On the SSH keys page, add a key:

    1. Click the Add key button.

      1. Enter the SSH key.
      2. Enter a User. Click Next.
  11. On the Timezone page, set your time zone settings:

    1. On the Timezone field, enter the time zone you want to add to your system image. For example, add the following time zone format: "US/Eastern".

      If you do not set a time zone, the system uses Universal Time, Coordinated (UTC) as default.

    2. Enter the NTP servers. Click Next.
  12. On the Locale page, complete the following steps:

    1. On the Keyboard search field, enter the package name you want to add to your system image. For example: ["en_US.UTF-8"].
    2. On the Languages search field, enter the package name you want to add to your system image. For example: "us". Click Next.
  13. On the Others page, complete the following steps:

    1. On the Hostname field, enter the hostname you want to add to your system image. If you do not add a hostname, the operating system determines the hostname.
    2. Mandatory only for the Simplifier Installer image: On the Installation Devices field, enter a valid node for your system image. For example: dev/sda1. Click Next.
  14. Mandatory only when building FIDO images: On the FIDO device onboarding page, complete the following steps:

    1. On the Manufacturing server URL field, enter the following information:

      1. On the DIUN public key insecure field, enter the insecure public key.
      2. On the DIUN public key hash field, enter the public key hash.
      3. On the DIUN public key root certs field, enter the public key root certs. Click Next.
  15. On the OpenSCAP page, complete the following steps:

    1. On the Datastream field, enter the datastream remediation instructions you want to add to your system image.
    2. On the Profile ID field, enter the profile_id security profile you want to add to your system image. Click Next.
  16. Mandatory only when building Ignition images: On the Ignition page, complete the following steps:

    1. On the Firstboot URL field, enter the package name you want to add to your system image.
    2. On the Embedded Data field, drag or upload your file. Click Next.
  17. . On the Review page, review the details about the blueprint. Click Create.

The RHEL image builder view opens, listing existing blueprints.

5.3. Importing a blueprint in the RHEL image builder web console interface

You can import and use an already existing blueprint. The system automatically resolves all the dependencies.

Prerequisites

  • You have opened the RHEL image builder app from the web console in a browser.
  • You have a blueprint that you want to import to use in the RHEL image builder web console interface.

Procedure

  1. On the RHEL image builder dashboard, click Import blueprint. The Import blueprint wizard opens.
  2. From the Upload field, either drag or upload an existing blueprint. This blueprint can be in either TOML or JSON format.
  3. Click Import. The dashboard lists the blueprint you imported.

Verification

When you click the blueprint you imported, you have access to a dashboard with all the customizations for the blueprint that you imported.

  • To verify the packages that have been selected for the imported blueprint, navigate to the Packages tab.

    • To list all the package dependencies, click All. The list is searchable and can be ordered.

Next steps

  • Optional: To modify any customization:

    • From the Customizations dashboard, click the customization you want to make a change. Optionally, you can click Edit blueprint to navigate to all the available customization options.

5.4. Exporting a blueprint from the RHEL image builder web console interface

You can export a blueprint to use the customizations in another system. You can export the blueprint in the TOML or in the JSON format. Both formats work on the CLI and also in the API interface.

Prerequisites

  • You have opened the RHEL image builder app from the web console in a browser.
  • You have a blueprint that you want to export.

Procedure

  1. On the image builder dashboard, select the blueprint you want to export.
  2. Click Export blueprint. The Export blueprint wizard opens.
  3. Click the Export button to download the blueprint as a file or click the Copy button to copy the blueprint to the clipboard.

    1. Optionally, click the Copy button to copy the blueprint.

Verification

  • Open the exported blueprint in a text editor to inspect and review it.

5.5. Creating a system image by using RHEL image builder in the web console interface

You can create a customized RHEL system image from a blueprint by completing the following steps.

Prerequisites

  • You opened the RHEL image builder app from the web console in a browser.
  • You created a blueprint.

Procedure

  1. In the RHEL image builder dashboard, click the blueprint tab.
  2. On the blueprint table, find the blueprint you want to build an image.
  3. On the right side of the chosen blueprint, click Create Image. The Create image dialog wizard opens.
  4. On the Image output page, complete the following steps:

    1. From the Select a blueprint list, select the image type you want.
    2. From the Image output type list, select the image output type you want.

      Depending on the image type you select, you need to add further details.

  5. Click Next.
  6. On the Review page, review the details about the image creation and click Create image.

    The image build starts and takes up to 20 minutes to complete.

Verification

After the image finishes building, you can:

  • Download the image.

    • On the RHEL image builder dashboard, click the Node options (⫶) menu and select Download image.
  • Download the logs of the image to inspect the elements and verify if any issue is found.

    • On the RHEL image builder dashboard, click the Node options (⫶) menu and select Download logs.

Chapter 6. Creating a boot ISO installer image with RHEL image builder

You can use RHEL image builder to create bootable ISO Installer images. These images consist of a .tar file that has a root file system. You can use the bootable ISO image to install the file system to a bare metal server.

RHEL image builder builds a manifest that creates a boot ISO that contains a root file system. To create the ISO image, select the image type image-installer. RHEL image builder builds a .tar file with the following content:

  • a standard Anaconda installer ISO
  • an embedded RHEL system tar file
  • a default Kickstart file that installs the commit with minimal default requirements

The created installer ISO image includes a pre-configured system image that you can install directly to a bare metal server.

6.1. Creating a boot ISO installer image using the RHEL image builder CLI

You can create a customized boot ISO installer image by using the RHEL image builder command-line interface. As a result, image builder builds an .iso file that contains a .tar file, which you can install for the Operating system. The .iso file is set up to boot Anaconda and install the .tar file to set up the system. You can use the created ISO image file on a hard disk or to boot in a virtual machine, for example, in an HTTP Boot or a USB installation.

Warning

The Installer (.iso) image type does not accept partitions customization. If you try to manually configure the filesystem customization, it is not applied to any system built by the Installer image. Mounting an ISO image built with RHEL image builder file system customizations causes an error in the Kickstart, and the installation does not reboot automatically. For more information, see Automate a RHEL ISO installation generated by image builder and Automate a RHEL ISO installation generated by image builder.

Prerequisites

  • You have created a blueprint for the image and customized it with a user included and pushed it back into RHEL image builder. See Blueprint customizations.

Procedure

  1. Create the ISO image:

    # composer-cli compose start BLUEPRINT-NAME image-installer
    • BLUEPRINT-NAME with name of the blueprint you created
    • image-installer is the image type

      The compose process starts in the background and the UUID of the compose is shown. Wait until the compose is finished. This might take several minutes.

  2. Check the status of the compose:

    # composer-cli compose status

    A finished compose shows a status value of FINISHED.

  3. Identify the compose in the list by its UUID.

    # composer-cli compose list
  4. After the compose is finished, download the created image file to the current directory:

    # composer-cli compose image UUID

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

    RHEL image builder builds a .iso file that contains a .tar file. The .tar file is the image that will be installed for the Operating system. The . iso is set up to boot Anaconda and install the .tar file to set up the system.

Next steps

In the directory where you downloaded the image file.

  1. Locate the .iso image you downloaded.
  2. Mount the ISO.

    $ mount -o ro path_to_ISO /mnt

    You can find the .tar file at the /mnt/liveimg.tar.gz directory.

  3. List the .tar file content:

    $ tar ztvf /mnt/liveimg.tar.gz

6.2. Creating a boot ISO installer image by using RHEL image builder in the GUI

You can build a customized boot ISO installer image by using the RHEL image builder GUI. You can use the resulting ISO image file on a hard disk or boot it in a virtual machine. For example, in an HTTP Boot or a USB installation.

Warning

The Installer (.iso) image type does not accept partitions customization. If you try to manually configure the filesystem customization, it is not applied to any system built by the Installer image. Mounting an ISO image built with RHEL image builder file system customizations causes an error in the Kickstart, and the installation does not reboot automatically. For more information, see Automate a RHEL ISO installation generated by image builder and Automate a RHEL ISO installation generated by image builder.

Prerequisites

Procedure

  1. On the RHEL image builder dashboard, locate the blueprint that you want to use to build your image. Optionally, enter the blueprint name or a part of it into the search box at upper left, and click Enter.
  2. On the right side of the blueprint, click the corresponding Create Image button.

    The Create image dialog wizard opens.

  3. On the Create image dialog wizard:

    1. In the Image Type list, select "RHEL Installer (.iso)".
    2. Click Next.
    3. On the Review tab, click Create.

      RHEL image builder adds the compose of a RHEL ISO image to the queue.

      After the process is complete, you can see the image build complete status. RHEL image builder creates the ISO image.

Verification

After the image is successfully created, you can download it.

  1. Click Download to save the "RHEL Installer (.iso)" image to your system.
  2. Navigate to the folder where you downloaded the "RHEL Installer (.iso)" image.
  3. Locate the .tar image you downloaded.
  4. Extract the "RHEL Installer (.iso)" image content.

    $ tar -xf content.tar

6.3. Installing a bootable ISO to a media and booting it

Install the bootable ISO image you created by using RHEL image builder to a bare metal system.

Prerequisites

Procedure

  1. Write the bootable ISO image directly to the USB drive using the dd tool. For example:

    dd if=installer.iso of=/dev/sdX

    Where installer.iso is the ISO image file name and /dev/sdX is your USB flash drive device path.

  2. Insert the flash drive into a USB port of the computer you want to boot.
  3. Boot the ISO image from the USB flash drive.

    When the installation environment starts, you might need to complete the installation manually, similarly to the default Red Hat Enterprise Linux installation.

Chapter 7. Creating pre-hardened images with RHEL image builder OpenSCAP integration

RHEL image builder on-premise supports the OpenSCAP integration. This integration enables the production of pre-hardened RHEL images. By setting up a blueprint, you can perform the following actions:

  • Customize it with a set of predefined security profiles
  • Add a set of packages or add-on files
  • Build a customized RHEL image ready to deploy on your chosen platform that is more suitable to your environment

Red Hat provides regularly updated versions of the security hardening profiles that you can choose when you build your systems so that you can meet your current deployment guidelines.

Warning

RHEL image builder does not include support for FIPS boot mode. Consequently, OpenSCAP profiles that require the FIPS mode to be enabled, such as DISA STIG, are not supported.

7.1. Differences between Kickstart and pre-hardened images

For the traditional image creation using a Kickstart file, you have to choose which packages you must install and ensure that the system is not affected by a vulnerability. With the RHEL image builder OpenSCAP integration, you can build security hardened images. During the image build process an OSBuild oscap remediation stage runs the OpenSCAP tool in the chroot, on the filesystem tree. The OpenSCAP tool runs the standard evaluation for the profile you choose and applies the remediations to the image. With this, you can build a more completely hardened image, if you compare it to running the remediation on a live system.

7.2. Installing OpenSCAP

Install the OpenSCAP tool to have access to SCAP tools to help you to create standard security checklists for your systems.

Procedure

  1. Install OpenSCAP on your system:

    # *dnf install openscap-scanner*
  2. Install scap-security-guide package:

    # *dnf install scap-security-guide*

    After the installation is completed you can start using the oscap command line tool. The SCAP content will be installed in the /usr/share/xml/scap/ssg/content/ directory.

7.3. The OpenSCAP blueprint customization

With the OpenSCAP support for blueprint customization, you can create blueprints and then use them to build your own pre-hardened images. To create a pre-hardened image you can customize the mount points and configure the file system layout according to the selected security profile. After you select the OpenSCAP profile, the OpenSCAP blueprint customization configures the image to trigger the remediation during the image build with the selected profile. During the image build, OpenSCAP applies a first-boot remediation.

To use the OpenSCAP blueprint customization in your image blueprints, you need to provide the following information:

  • The datastream path to the datastream remediation instructions. The datastream path is located in the /usr/share/xml/scap/ssg/content/ directory.
  • The profile_id of the required security profile. The value of the profile_id field accepts both the long and short forms, for example, the following are acceptable: cis or xccdf_org.ssgproject.content_profile_cis. See SCAP Security Guide profiles supported in RHEL 9 for more details.

    The following is a blueprint with OpenSCAP customization example:

    [customizations]
    datastream = "/usr/share/xml/scap/ssg/content/ssg-rhel8-ds.xml"
    profile_id = "xccdf_org.ssgproject.content_profile_cis"

    The most common SCAP file type is an SCAP source datastream. You can find more details about the SCAP source datastream from the scap-security-guide package, enter the command:

    $ oscap info /usr/share/xml/scap/ssg/content/ssg-rhel8-ds.xml

The oscap tool runs on the image tree to perform an offline scan of a file system that is mounted at an arbitrary path. You can use it for scanning of custom objects that are not supported by oscap-docker or oscap-vm, such as containers in formats other than Docker. oscap-chroot mimics the usage and options of the oscap tool.

RHEL image builder generates the necessary configurations for the osbuild stage based on your blueprint customization. Additionally, RHEL image builder adds two packages to the image:

  • openscap-scanner - the OpenSCAP tool.
  • scap-security-guide - package which contains the remediation instructions.

    Note

    The remediation stage uses the scap-security-guide package for the datastream because this package is installed on the image by default. If you want to use a different datastream, add the necessary package to the blueprint, and specify the path to the datastream in the oscap configuration.

7.4. Creating a pre-hardened image with RHEL image builder

With the OpenSCAP and RHEL image builder integration, you can create pre-hardened images that you can deploy in a VM.

Prerequisite

  • You are logged in as the root user or a user who is a member of the welder group.

Procedure

  1. Create a blueprint in the TOML format, with the following content:

    name = "blueprint_name"
    description = "blueprint_description"
    version = "0.0.1"
    modules = []
    groups = []
    distro = ""
    
    [customizations]
    [[customizations.user]]
    name = "scap-security-guide"
    description = "Admin account"
    password = secure_password_hash
    key = ssh-key
    home = "/home/scap-security-guide"
    group = ["wheel"]
    
    [[customizations.filesystem]]
    mountpoint = "/tmp"
    size = "20 GiB"
    
    [customizations.openscap]
    datastream = "/usr/share/xml/scap/ssg/content/ssg-rhel8-ds.xml "
    profile_id = "cis"
  2. Start the build of a OpenSCAP image:

    # composer-cli compose start blueprint_name qcow2

    Where blueprint_name is the blueprint name.

    After the image build is ready, you can use your pre-hardened image on your deployments. See Creating a virtual machine.

Verification

After you deploy your pre-hardened image in a VM, you can perform a configuration compliance scan to verify that the image is aligned to the selected security profile.

Important

Performing a configuration compliance scanning does not guarantee the system is compliant. For more information, see Configuration compliance scanning.

  1. Connect to the image using SSH.
  2. Run the oscap scanner.

    # scap-workbench
  3. On the SCAP Workbench:

    1. Select the version of the system you want to scan. Click Load content.
    2. Select the profile you want to scan and click Scan. OpenSCAP checks all the requirements for the system.
    3. Click Scan to scan your system with the selected profile.
    4. After the scan finishes, click Show Report.

Chapter 8. Preparing and deploying a KVM Guest Image by using RHEL image builder

Use RHEL image builder to create a .qcow2 purpose-built that you can deploy on a Kernel-based Virtual Machine (KVM) based hypervisor.

Creating a customized KVM guest image involves the following high-level steps:

  1. Create a blueprint for the .qcow2 image.
  2. Create a .qcow2 image by using RHEL image builder.
  3. Create a virtual machine from the KVM guest image.

8.1. Creating customized KVM guest images by using RHEL image builder

You can create a customized .qcow2 KVM guest image by using RHEL image builder. The following procedure shows the steps on the GUI, but you can also use the CLI.

Prerequisites

  • You must be in the root or weldr group to access the system.
  • The cockpit-composer package is installed.
  • On a RHEL system, you have opened the RHEL image builder dashboard of the web console.
  • You have created a blueprint. See Creating a blueprint in the web console interface.

Procedure

  1. Click the blueprint name you created.
  2. Select the tab Images.
  3. Click Create Image to create your customized image. The Create Image window opens.
  4. From the Type drop-down menu list, select QEMU Image(.qcow2).
  5. Set the size that you want the image to be when instantiated and click Create.
  6. A small pop-up on the upper right side of the window informs you that the image creation has been added to the queue. After the image creation process is complete, you can see the Image build complete status.

Verification

  • Click the breadcrumbs icon and select the Download option. RHEL image builder downloads the KVM guest image .qcow2 file at your default download location.

8.2. Creating a virtual machine from a KVM guest image

With RHEL image builder, you can build a .qcow2 image, and use a KVM guest image to create a VM. The KVM guest images created using RHEL image builder already have cloud-init installed and enabled.

Prerequisites

  • You created a .qcow2 image by using RHEL image builder. See Creating a blueprint in the web console interface.
  • You have the qemu-kvm package installed on your system. You can check if the /dev/kvm device is available on your system, and virtualization features are enabled in the BIOS.
  • You have the libvirt and virt-install packages installed on your system.
  • You have the genisoimage utility, that is provided by the xorriso package, installed on your system.

Procedure

  1. Move the .qcow2 image that you created by using RHEL image builder to the /var/lib/libvirt/images/ directory.
  2. Create a directory, for example, cloudinitiso and navigate to this newly created directory:

    $ mkdir cloudinitiso
    $ cd cloudinitiso
  3. Create a file named meta-data. Add the following information to this file:

    instance-id: citest
    local-hostname: vmname
  4. Create a file named user-data. Add the following information to the file:

    #cloud-config
    user: admin
    password: password
    chpasswd: {expire: False}
    ssh_pwauth: True
    ssh_authorized_keys:
      - ssh-rsa AAA...fhHQ== your.email@example.com

    ssh_authorized_keys is your SSH public key. You can find your SSH public key in ~/.ssh/<id_rsa.pub>\.

  5. Use the genisoimage utility to create an ISO image that includes the user-data and meta-data files.

    # genisoimage -output cloud-init.iso -volid cidata -joliet -rock user-data meta-data
    
    I: -input-charset not specified, using utf-8 (detected in locale settings)
    Total translation table size: 0
    Total rockridge attributes bytes: 331
    Total directory bytes: 0
    Path table size(bytes): 10
    Max brk space used 0
    183 extents written (0 MB)
  6. Create a new VM from the KVM Guest Image using the virt-install command. Include the ISO image you created on step 4 as an attachment to the VM image.

    # virt-install \
        --memory 4096 \
        --vcpus 4 \
        --name myvm \
        --disk rhel-9-x86_64-kvm.qcow2,device=disk,bus=virtio,format=qcow2 \
        --disk cloud-init.iso,device=cdrom \
        --os-variant rhel 9 \
        --virt-type kvm \
        --graphics none \
        --import
    • --graphics none - means it is a headless RHEL 9 VM.
    • --vcpus 4 - means that it uses 4 virtual CPUs.
    • --memory 4096 - means it uses 4096 MB RAM.
  7. The VM installation starts:

    Starting install...
    Connected to domain mytestcivm
    ...
    [  OK  ] Started Execute cloud user/final scripts.
    [  OK  ] Reached target Cloud-init target.
    
    Red Hat Enterprise Linux 9 (Ootpa)
    Kernel 4.18.0-221.el8.x86_64 on an x86_64

Verification

After the boot is complete, the VM shows a text login interface. To log in to the local console of the VM, use user the details from the user-data file:

  1. Enter admin as a username and press Enter.
  2. Enter password as password and press Enter.

    After the login authentication is complete, you have access to the VM using the CLI.

Chapter 9. Pushing a container to a registry and embedding it into an image

With RHEL image builder, you can build security hardened images using the OpenSCAP tool. You can take advantage of the support for container customization in the blueprints to create a container and embed it directly into the image you create.

9.1. Blueprint customization to embed a container into an image

To embed a container from registry.access.redhat.com registry, you must add a container customization to your blueprint. For example:

[[containers]]
source = "registry.access.redhat.com/ubi9/ubi:latest"
name =  "local-name"
tls-verify = true
  • source - Mandatory field. It is a reference to the container image at a registry. This example uses the registry.access.redhat.com registry. You can specify a tag version. The default tag version is latest.
  • name - The name of the container in the local registry.
  • tls-verify - Boolean field. The tls-verify boolean field controls the transport layer security. The default value is true.

    RHEL image builder pulls the container during the image build and stores the container into the image. The default local container storage location depends on the image type, so that all support container-tools, such as Podman, are able to work with it. The embedded containers are not started. To access protected container resources, you can use a containers-auth.json file.

9.2. The Container registry credentials

The osbuild-worker service is responsible for the communication with the container registry. To enable that, you can set up the /etc/osbuild-worker/osbuild-worker.toml configuration file.

Note

After setting the /etc/osbuild-worker/osbuild-worker.toml configuration file, you must restart the osbuild-worker service, because it reads the /etc/osbuild-worker/osbuild-worker.toml configuration file only once, during the osbuild-worker service start.

The /etc/osbuild-worker/osbuild-worker.toml configuration file has a containers section with an auth_field_path entry that is a string referring to a path of a containers-auth.json file to be used for accessing protected resources. The container registry credentials are only used to pull a container image from a registry, when embedding the container into the image.

For example:

[containers]
auth_file_path = "/etc/osbuild-worker/containers-auth.json"

Additional resources

  • The containers-auth.json man page

9.3. Pushing a container artifact directly to a container registry

You can push container artifacts, such as RHEL for Edge container images directly, directly to a container registry after you build it, by using the RHEL image builder CLI.

Prerequisites

  • Access to quay.io registry. This example uses the quay.io container registry as a target registry, but you can use a container registry of your choice.

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. Push the blueprint:

    # composer-cli blueprints push blueprint.toml
  4. Build the container image, by passing the registry and the repository to the composer-cli tool as arguments.

    # composer-cli compose start simple-container container "quay.io:8080/osbuild/repository" registry-config.toml
    • simple-container - is the blueprint name.
    • container - is the image type.
    • "quay.io:8080/osbuild/repository" - quay.io is the target registry, osbuild is the organization and repository is the location to push the container when it finishes building. Optionally, you can set a tag. If you do not set a value for :tag, it uses :latest tag by default.

      Note

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

  5. 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.

Additional resources

9.4. Building an image and pulling the container into the image

After you have created the container image, you can build your customized image and pull the container image into it. For that, you must specify a container customization in the blueprint, and the container name for the final image. During the build process, the container image is fetched and placed in the local Podman container storage.

Prerequisites

Procedure

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

    name = "image"
    description = "A qcow2 image with a container"
    version = "0.0.1"
    distro = "rhel-90"
    
    [[packages]]
    name = "podman"
    version = "*"
    
    [[containers]]
    source = "registry.access.redhat.com/ubi9:8080/osbuild/container/container-image@sha256:manifest-ID-from-Repository-tag: tag-version"
    name =  "source-name"
    tls-verify = true
  2. Push the blueprint:

    # composer-cli blueprints push blueprint-image.toml
  3. Build the container image:

    # composer-cli start compose image qcow2
    • image is the blueprint name.
    • qcow2 is the image type.

      Note

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

  4. To check the status of the compose:

    # composer-cli compose status

    A finished compose shows the FINISHED status value. To identify your compose in the list, use its UUID.

  5. After the compose process is finished, download the resulting image file to your default download location:

    # composer-cli compose image UUID

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

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

Verification

From the resulting qcow2 image that you downloaded, perform the following steps:

  1. Start the qcow2 image in a VM. See Creating a virtual machine from a KVM guest image.
  2. The qemu wizard opens. Login in to the qcow2 image.

    1. Enter 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.
  3. Run the container image and open a shell prompt inside the container:

    # podman run -it registry.access.redhat.com/ubi9:8080/osbuild/repository /bin/bash/

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

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

    # type -a nginx

    The output shows you the nginx package path.

Chapter 10. Preparing and uploading cloud images by using RHEL image builder

RHEL image builder can create custom system images ready for use on various cloud platforms. To use your customized RHEL system image in a cloud, create the system image with RHEL image builder using the chosen output type, configure your system for uploading the image, and upload the image to your cloud account. You can push customized image clouds through the Image Builder application in the RHEL web console, available for a subset of the service providers that we support, such as AWS and Microsoft Azure clouds. See Pushing images to AWS Cloud AMI and Pushing VHD images to Microsoft Azure cloud.

10.1. Preparing to upload AWS AMI images

Before uploading an AWS AMI image, you must configure a system for uploading the images.

Prerequisites

Procedure

  1. Install Python 3 and the pip tool:

    # dnf install python3 python3-pip
  2. Install the AWS command-line tools with pip:

    # pip3 install awscli
  3. Run the following command to set your profile. The terminal prompts you to provide your credentials, region and output format:

    $ aws configure
    AWS Access Key ID [None]:
    AWS Secret Access Key [None]:
    Default region name [None]:
    Default output format [None]:
  4. Define a name for your bucket and use the following command to create a bucket:

    $ BUCKET=bucketname
    $ aws s3 mb s3://$BUCKET

    Replace bucketname with the actual bucket name. It must be a globally unique name. As a result, your bucket is created.

  5. To grant permission to access the S3 bucket, create a vmimport S3 Role in the AWS Identity and Access Management (IAM), if you have not already done so in the past:

    1. Create a trust-policy.json file with the trust policy configuration, in the JSON format. For example:

      {
          "Version": "2022-10-17",
          "Statement": [{
              "Effect": "Allow",
              "Principal": {
                  "Service": "vmie.amazonaws.com"
              },
              "Action": "sts:AssumeRole",
              "Condition": {
                  "StringEquals": {
                      "sts:Externalid": "vmimport"
                  }
              }
          }]
      }
    2. Create a role-policy.json file with the role policy configuration, in the JSON format. For example:

      {
          "Version": "2012-10-17",
          "Statement": [{
              "Effect": "Allow",
              "Action": ["s3:GetBucketLocation", "s3:GetObject", "s3:ListBucket"],
              "Resource": ["arn:aws:s3:::%s", "arn:aws:s3:::%s/"] }, { "Effect": "Allow", "Action": ["ec2:ModifySnapshotAttribute", "ec2:CopySnapshot", "ec2:RegisterImage", "ec2:Describe"],
              "Resource": "*"
          }]
      }
      $BUCKET $BUCKET
    3. Create a role for your Amazon Web Services account, by using the trust-policy.json file:

      $ aws iam create-role --role-name vmimport --assume-role-policy-document file://trust-policy.json
    4. Embed an inline policy document, by using the role-policy.json file:

      $ aws iam put-role-policy --role-name vmimport --policy-name vmimport --policy-document file://role-policy.json

10.2. Uploading an AMI image to AWS by using the CLI

You can use RHEL image builder to build ami images and push them directly to Amazon AWS Cloud service provider, by using the CLI.

Prerequisites

  • You have an Access Key ID configured in the AWS IAM account manager.
  • You have a writable S3 bucket prepared.
  • You have a defined blueprint.

Procedure

  1. Using the text editor, create a configuration file with the following content:

    provider = "aws"
    
    [settings]
    accessKeyID = "AWS_ACCESS_KEY_ID"
    secretAccessKey = "AWS_SECRET_ACCESS_KEY"
    bucket = "AWS_BUCKET"
    region = "AWS_REGION"
    key = "IMAGE_KEY"

    Replace values in the fields with your credentials for accessKeyID, secretAccessKey, bucket, and region. The IMAGE_KEY value is the name of your VM Image to be uploaded to EC2.

  2. Save the file as CONFIGURATION-FILE.toml and close the text editor.
  3. Start the compose to upload it to AWS:

    # composer-cli compose start blueprint-name image-type image-key configuration-file.toml

    Replace:

    • blueprint-name with the name of the blueprint you created
    • image-type with the ami image type.
    • image-key with the name of your VM Image to be uploaded to EC2.
    • configuration-file.tomlwith the name of the configuration file of the cloud provider.

      Note

      You must have the correct AWS Identity and Access Management (IAM) settings for the bucket you are going to send your customized image to. You have to set up a policy to your bucket before you are able to upload images to it.

  4. Check the status of the image build:

    # composer-cli compose status

    After the image upload process is complete, you can see the "FINISHED" status.

Verification

To confirm that the image upload was successful:

  1. Access EC2 on the menu and select the correct region in the AWS console. The image must have the available status, to indicate that it was successfully uploaded.
  2. On the dashboard, select your image and click Launch.

10.3. Pushing images to AWS Cloud AMI

You can create a (.raw) image by using RHEL image builder, and choose to check the Upload to AWS checkbox to push the output image that you create directly to the Amazon AWS Cloud AMI service provider.

Prerequisites

  • You must have root or wheel group user access to the system.
  • You have opened the RHEL image builder interface of the RHEL web console in a browser.
  • You have created a blueprint. See Creating a blueprint in the web console interface.
  • You must have an Access Key ID configured in the AWS IAM account manager.
  • You must have a writable S3 bucket prepared.

Procedure

  1. In the RHEL image builder dashboard, click the blueprint name that you previously created.
  2. Select the tab Images.
  3. Click Create Image to create your customized image.

    The Create Image window opens.

    1. From the Type drop-down menu list, select Amazon Machine Image Disk (.raw).
    2. Check the Upload to AWS checkbox to upload your image to the AWS Cloud and click Next.
    3. To authenticate your access to AWS, type your AWS access key ID and AWS secret access key in the corresponding fields. Click Next.

      Note

      You can view your AWS secret access key only when you create a new Access Key ID. If you do not know your Secret Key, generate a new Access Key ID.

    4. Type the name of the image in the Image name field, type the Amazon bucket name in the Amazon S3 bucket name field and type the AWS region field for the bucket you are going to add your customized image to. Click Next.
    5. Review the information and click Finish.

      Optionally, click Back to modify any incorrect detail.

      Note

      You must have the correct IAM settings for the bucket you are going to send your customized image. This procedure uses the IAM Import and Export, so you have to set up a policy to your bucket before you are able to upload images to it. For more information, see Required Permissions for IAM Users.

  4. A pop-up on the upper right informs you of the saving progress. It also informs that the image creation has been initiated, the progress of this image creation and the subsequent upload to the AWS Cloud.

    After the process is complete, you can see the Image build complete status.

  5. In a browser, access Service→EC2.

    1. On the AWS console dashboard menu, choose the correct region. The image must have the Available status, to indicate that it is uploaded.
    2. On the AWS dashboard, select your image and click Launch.
  6. A new window opens. Choose an instance type according to the resources you need to start your image. Click Review and Launch.
  7. Review your instance start details. You can edit each section if you need to make any changes. Click Launch
  8. Before you start the instance, select a public key to access it.

    You can either use the key pair you already have or you can create a new key pair.

    Follow the next steps to create a new key pair in EC2 and attach it to the new instance.

    1. From the drop-down menu list, select Create a new key pair.
    2. Enter the name to the new key pair. It generates a new key pair.
    3. Click Download Key Pair to save the new key pair on your local system.
  9. Then, you can click Launch Instance to start your instance.

    You can check the status of the instance, which displays as Initializing.

  10. After the instance status is running, the Connect button becomes available.
  11. Click Connect. A window appears with instructions on how to connect by using SSH.

    1. Select A standalone SSH client as the preferred connection method to and open a terminal.
    2. In the location you store your private key, ensure that your key is publicly viewable for SSH to work. To do so, run the command:

      $ chmod 400 _your-instance-name.pem_&gt;
    3. Connect to your instance by using its Public DNS:

      $ ssh -i &lt;_your-instance-name.pem_&gt; ec2-user@&lt;_your-instance-IP-address_&gt;
    4. Type yes to confirm that you want to continue connecting.

      As a result, you are connected to your instance over SSH.

Verification

  • Check if you are able to perform any action while connected to your instance by using SSH.

10.4. Preparing to upload Microsoft Azure VHD images

You can use RHEL image builder to create a VHD image that can be uploaded to Microsoft Azure cloud.

Prerequisites

  • You must have a Microsoft Azure resource group and storage account.
  • You have Python installed. The AZ CLI tool depends on python.

Procedure

  1. Import the Microsoft repository key:

    # rpm --import https://packages.microsoft.com/keys/microsoft.asc
  2. Create a local azure-cli.repo repository with the following information. Save the azure-cli.repo repository under /etc/yum.repos.d/:

    [azure-cli]
    name=Azure CLI
    baseurl=https://packages.microsoft.com/yumrepos/vscode
    enabled=1
    gpgcheck=1
    gpgkey=https://packages.microsoft.com/keys/microsoft.asc
  3. Install the Microsoft Azure CLI:

    # dnfdownloader azure-cli
    # rpm -ivh --nodeps azure-cli-2.0.64-1.el7.x86_64.rpm
    Note

    The downloaded version of the Microsoft Azure CLI package can vary depending on the current available version.

  4. Run the Microsoft Azure CLI:

    $ az login

    The terminal shows the following message Note, we have launched a browser for you to login. For old experience with device code, use "az login --use-device-code. Then, the terminal opens a browser with a link to https://microsoft.com/devicelogin from where you can login.

    Note

    If you are running a remote (SSH) session, the login page link will not open in the browser. In this case, you can copy the link to a browser and login to authenticate your remote session. To sign in, use a web browser to open the page https://microsoft.com/devicelogin and enter the device code to authenticate.

  5. List the keys for the storage account in Microsoft Azure:

    $ az storage account keys list --resource-group <resource_group_name> --account-name <storage_account_name>

    Replace resource-group-name with name of your Microsoft Azure resource group and storage-account-name with name of your Microsoft Azure storage account.

    Note

    You can list the available resources using the following command:

    $ az resource list

Make note of value key1 in the output of the previous command.

  1. Create a storage container:

    $ az storage container create --account-name <storage_account_name>\
    --account-key <key1_value> --name <storage_account_name>

    Replace storage-account-name with name of the storage account.

Additional resources

10.5. Uploading VHD images to Microsoft Azure cloud

After you have created your customized VHD image, you can upload it to the Microsoft Azure cloud.

Prerequisites

  • Your system must be set up for uploading Microsoft Azure VHD images. See Preparing to upload Microsoft Azure VHD images.
  • You must have a Microsoft Azure VHD image created by RHEL image builder.

    • In the CLI, use the vhd output type. NOTE: When creating a .vhd image using the CLI, image builder writes temporary files to the /var subdirectory. To prevent the .vhd image creation from failing, increase the /var subdirectory capacity to at least 15 to 20 GB free space to ensure availability.
    • In the GUI, use the Azure Disk Image (.vhd) image type.

Procedure

  1. Push the image to Microsoft Azure and create an instance from it:

    $ az storage blob upload --account-name <account_name> --container-name <container_name> --file <_image_-disk.vhd> --name <_image_-disk.vhd> --type page
    ...
  2. After the upload to the Microsoft Azure Blob storage completes, create a Microsoft Azure image from it:

    $ az image create --resource-group &lt; _resource_group_name_&gt; --name &lt;_image_-disk.vhd&gt;  --os-type linux --location eastus --source https://$ACCOUNT.blob.core.windows.net/&lt;_container_name_&gt; &lt;_image_-disk.vhd&gt;
     - Running ...

Verification

  1. Create an instance either with the Microsoft Azure portal, or a command similar to the following:

    $ az vm create --resource-group &lt;_resource_group_name_&gt; --location eastus --name &lt;_image_-disk.vhd&gt; --image &lt;_image_-disk.vhd&gt; --admin-username azure-user --generate-ssh-keys
     - Running ...
  2. Use your private key via SSH to access the resulting instance. Log in as azure-user. This username was set on the previous step.

10.6. Pushing VHD images to Microsoft Azure cloud

You can create .vhd images by using RHEL image builder. Then, you can push the output .vhd images to a Blob Storage of the Microsoft Azure Cloud service provider.

Prerequisites

Procedure

  1. In the RHEL image builder dashboard, select the blueprint you want to use.
  2. Click the Images tab.
  3. Click Create Image to create your customized .vhd image.

    The Create image wizard opens.

    1. Select Microsoft Azure (.vhd) from the Type drop-down menu list.
    2. Check the Upload to Azure checkbox to upload your image to the Microsoft Azure Cloud.
    3. Enter the Image Size and click Next.
  4. On the Upload to Azure page, enter the following information:

    1. On the Authentication page, enter:

      1. Your Storage account name. You can find it on the Storage account page, in the Microsoft Azure portal.
      2. Your Storage access key: You can find it on the Access Key Storage page.
      3. Click Next.
    2. On the Authentication page, enter:

      1. The image name.
      2. The Storage container. It is the blob container to which you will upload the image. Find it under the Blob service section, in the Microsoft Azure portal.
      3. Click Next.
  5. On the Review page, click Create. The RHEL image builder and upload processes start.

    Access the image you pushed into Microsoft Azure Cloud.

  6. Access the Microsoft Azure portal.
  7. In the search bar, type "storage account" and click Storage accounts from the list.
  8. On the search bar, type "Images" and select the first entry under Services. You are redirected to the Image dashboard.
  9. On the navigation panel, click Containers.
  10. Find the container you created. Inside the container is the .vhd file you created and pushed by using RHEL image builder.

Verification

  1. Verify that you can create a VM image and launch it.

    1. In the search bar, type images account and click Images from the list.
    2. Click +Create.
    3. From the dropdown list, choose the resource group you used earlier.
    4. Enter a name for the image.
    5. For the OS type, select Linux.
    6. For the VM generation, select Gen 2.
    7. Under Storage Blob, click Browse and click through the storage accounts and container until you reach your VHD file.
    8. Click Select at the end of the page.
    9. Choose an Account Type, for example, Standard SSD.
    10. Click Review + Create and then Create. Wait a few moments for the image creation.
  2. To launch the VM, follow the steps:

    1. Click Go to resource.
    2. Click + Create VM from the menu bar on the header.
    3. Enter a name for your virtual machine.
    4. Complete the Size and Administrator account sections.
    5. Click Review + Create and then Create. You can see the deployment progress.

      After the deployment finishes, click the virtual machine name to retrieve the public IP address of the instance to connect by using SSH.

    6. Open a terminal to create an SSH connection to connect to the VM.

10.7. Creating a customized RHEL VMDK system image by using RHEL image builder

With RHEL image builder, you can create customized system images in the Open virtualization format (.ova). You can upload these images to the VMware vSphere client. The Open virtualization format (.ova) is a .vmdk image with additional metadata about the virtual hardware, which contains a minimal template. After importing the .ova image to the vSphere client, you can configure it with any additional hardware, such as network, disks, and CD ROMS.

You can import the Open virtualization format (.ova) image by using either the vSphere GUI or the govc client. To upload the image by using the govc client, see Uploading VMDK images and creating a RHEL virtual machine in vSphere.

Prerequisites

  • You opened the RHEL image builder app from the web console in a browser.
  • You created a blueprint.

Procedure

  1. In the RHEL image builder dashboard, click the Blueprint tab.
  2. On the blueprint table, find the blueprint you want to build an image.
  3. On the right side of the chosen blueprint, click Create Image. The Create image dialog wizard opens.
  4. On the Image output page, complete the following steps:

    1. From the Select a blueprint list, select the image type you want.
    2. From the Image output type list, select the image output type you want.
    3. Optional: Check Upload to VMWare checkbox to upload the image directly to VMware.
    4. Enter a size for the image.
    5. Click Next.
  5. On the Upload to VMware page, enter the following information:

    1. Image name: Enter the image name.
    2. Host: Enter the VMware vSphere instance URL where the image file will be uploaded.
    3. Cluster: Enter the cluster name page to which the image will be uploaded.
    4. Datacenter: Datacenter name to which the image will be uploaded.
    5. Datastore: Datastore name to which the image will be uploaded.
    6. Folder: Folder name to which the image will be uploaded.
    7. Click Next.
  6. On the Review page, review the details about the image creation and click Create.

    The image creation starts, the progress of this image creation and the subsequent upload to the VMware vSphere client.

10.8. Uploading VMDK images and creating a RHEL virtual machine in vSphere

With RHEL image builder, you can create customized VMware vSphere system images, either in the Open virtualization format (.ova) or in the Virtual disk (.vmdk) format. You can upload these images to the VMware vSphere client. You can upload the .vmdk or .ova image to VMware vSphere using the govc import.vmdk CLI tool. The vmdk you create contains the cloud-init package installed and you can use it to provision users by using user data, for example.

Note

Uploading vmdk images by using the VMware vSphere GUI is not supported.

Prerequisites

  • You created a blueprint with username and password customizations.
  • You created a VMware vSphere image either in the .ova or .vmdk format by using RHEL image builder and downloaded it to your host system.
  • You installed and configured the govc CLI tool, to be able use the import.vmdk command.

Procedure

  1. Configure the following values in the user environment with the GOVC environment variables:

    GOVC_URL
    GOVC_DATACENTER
    GOVC_FOLDER
    GOVC_DATASTORE
    GOVC_RESOURCE_POOL
    GOVC_NETWORK
  2. Navigate to the directory where you downloaded your VMware vSphere image.
  3. Launch the VMware vSphere image on vSphere by following the steps:

    1. Import the VMware vSphere image in to vSphere:

      $ govc import.vmdk ./composer-api.vmdk foldername

      For the .ova format:

      $ govc import.ova ./composer-api.ova foldername
    2. Create the VM in vSphere without powering it on:

      govc vm.create \
      -net.adapter=vmxnet3 \
      -m=4096 -c=2 -g=rhel8_64Guest \
      -firmware=efi -disk=”foldername/composer-api.vmdk” \
      -disk.controller=scsi -on=false \
       vmname

      For the .ova format, replace the line -firmware=efi -disk=”foldername/composer-api.vmdk” \ with `-firmware=efi -disk=”foldername/composer-api.ova” \

    3. Power-on the VM:

      govc vm.power -on vmname
    4. Retrieve the VM IP address:

      govc vm.ip vmname
    5. Use SSH to log in to the VM, using the username and password you specified in your blueprint:

      $ ssh admin@<_ip_address_of_the_vm_>
      Note

      If you copied the .vmdk image from your local host to the destination using the govc datastore.upload command, using the resulting image is not supported. There is no option to use the import.vmdk command in the vSphere GUI and as a result, the vSphere GUI does not support the direct upload. As a consequence, the .vmdk image is not usable from the vSphere GUI.

10.9. Uploading images to GCP with RHEL image builder

With RHEL image builder, you can build a gce image, provide credentials for your user or GCP service account, and then upload the gce image directly to the GCP environment.

10.9.1. Uploading a gce image to GCP by using the CLI

Follow the procedure to set up a configuration file with credentials to upload your gce image to GCP.

+ WARNING: You cannot manually import gce image to GCP, because the image will not boot. You must use either gcloud or RHEL image builder to upload it.

Prerequisites

  • You have a valid Google account and credentials to upload your image to GCP. The credentials can be from a user account or a service account. The account associated with the credentials must have at least the following IAM roles assigned:

    • roles/storage.admin - to create and delete storage objects
    • roles/compute.storageAdmin - to import a VM image to Compute Engine.
  • You have an existing GCP bucket.

Procedure

  1. By using a text editor, create a gcp-config.toml configuration file with the following content:

    provider = "gcp"
    
    [settings]
    bucket = "GCP_BUCKET"
    region = "GCP_STORAGE_REGION"
    object = "OBJECT_KEY"
    credentials = "GCP_CREDENTIALS"
    • GCP_BUCKET points to an existing bucket. It is used to store the intermediate storage object of the image which is being uploaded.
    • GCP_STORAGE_REGION is both a regular Google storage region and, a dual or multi region.
    • OBJECT_KEY is the name of an intermediate storage object. It must not exist before the upload, and it is deleted when the upload process is done. If the object name does not end with .tar.gz, the extension is automatically added to the object name.
    • GCP_CREDENTIALS is a Base64-encoded scheme of the credentials JSON file downloaded from GCP. The credentials determine which project the GCP uploads the image to.

      Note

      Specifying GCP_CREDENTIALS in the gcp-config.toml file is optional if you use a different mechanism to authenticate with GCP. For other authentication methods, see Authenticating with GCP.

  2. Retrieve the GCP_CREDENTIALS from the JSON file downloaded from GCP.

    $ sudo base64 -w 0 cee-gcp-nasa-476a1fa485b7.json
  3. Create a compose with an additional image name and cloud provider profile:

    $ sudo composer-cli compose start BLUEPRINT-NAME gce IMAGE_KEY gcp-config.toml

    The image build, upload, and cloud registration processes can take up to ten minutes to complete.

Verification

  • Verify that the image status is FINISHED:

    $ sudo composer-cli compose status

10.9.2. How RHEL image builder sorts the authentication order of different GCP credentials

You can use several different types of credentials with RHEL image builder to authenticate with GCP. If RHEL image builder configuration is set to authenticate with GCP using multiple sets of credentials, it uses the credentials in the following order of preference:

  1. Credentials specified with the composer-cli command in the configuration file.
  2. Credentials configured in the osbuild-composer worker configuration.
  3. Application Default Credentials from the Google GCP SDK library, which tries to automatically find a way to authenticate by using the following options:

    1. If the GOOGLE_APPLICATION_CREDENTIALS environment variable is set, Application Default Credentials tries to load and use credentials from the file pointed to by the variable.
    2. Application Default Credentials tries to authenticate by using the service account attached to the resource that is running the code. For example, Google Compute Engine VM.

      Note

      You must use the GCP credentials to determine which GCP project to upload the image to. Therefore, unless you want to upload all of your images to the same GCP project, you always must specify the credentials in the gcp-config.toml configuration file with the composer-cli command.

10.9.2.1. Specifying GCP credentials with the composer-cli command

You can specify GCP authentication credentials in the upload target configuration gcp-config.toml file. Use a Base64-encoded scheme of the Google account credentials JSON file to save time.

Procedure

  1. Get the encoded content of the Google account credentials file with the path stored in GOOGLE_APPLICATION_CREDENTIALS environment variable, by running the following command:

    $ base64 -w 0 "${GOOGLE_APPLICATION_CREDENTIALS}"
  2. In the upload target configuration gcp-config.toml file, set the credentials:

    provider = "gcp"
    
    [settings]
    provider = "gcp"
    
    [settings]
    ...
    credentials = "GCP_CREDENTIALS"

10.9.2.2. Specifying credentials in the osbuild-composer worker configuration

You can configure GCP authentication credentials to be used for GCP globally for all image builds. This way, if you want to import images to the same GCP project, you can use the same credentials for all image uploads to GCP.

Procedure

  • In the /etc/osbuild-worker/osbuild-worker.toml worker configuration, set the following credential value:

    [gcp]
    credentials = "PATH_TO_GCP_ACCOUNT_CREDENTIALS"

10.10. Pushing VMDK images to vSphere using the RHEL image builder GUI tool

You can build VMware images by using the RHEL image builder GUI tool and push the images directly to your vSphere instance, to avoid having to download the image file and push it manually. The vmdk you create contains the cloud-init package installed and you can use it to provision users by using user data, for example. To build .vmdk images by using RHEL image builder and push them directly to vSphere instances service provider, follow the steps:

Prerequisites

Procedure

  1. For the blueprint you created, click the Images tab .
  2. Click Create Image to create your customized image.

    The Image type window opens.

  3. In the Image type window:

    1. From the dropdown menu, select the Type: VMware vSphere (.vmdk).
    2. Check the Upload to VMware checkbox to upload your image to the vSphere.
    3. Optional: Set the size of the image you want to instantiate. The minimal default size is 2 GB.
    4. Click Next.
  4. In the Upload to VMware window, under Authentication, enter the following details:

    1. Username: username of the vSphere account.
    2. Password: password of the vSphere account.
  5. In the Upload to VMware window, under Destination, enter the following details about the image upload destination:

    1. Image name: a name for the image.
    2. Host: The URL of your VMware vSphere.
    3. Cluster: The name of the cluster.
    4. Data center: The name of the data center.
    5. Data store:The name of the Data store.
    6. Click Next.
  6. In the Review window, review the details of the image creation and click Finish.

    You can click Back to modify any incorrect detail.

    RHEL image builder adds the compose of a RHEL vSphere image to the queue, and creates and uploads the image to the Cluster on the vSphere instance you specified.

    Note

    The image build and upload processes take a few minutes to complete.

    After the process is complete, you can see the Image build complete status.

Verification

After the image status upload is completed successfully, you can create a Virtual Machine (VM) from the image you uploaded and login into it. To do so:

  1. Access VMware vSphere Client.
  2. Search for the image in the Cluster on the vSphere instance you specified.
  3. Select the image you uploaded.
  4. Right-click the selected image.
  5. Click New Virtual Machine.

    A New Virtual Machine window opens.

    In the New Virtual Machine window, provide the following details:

    1. Select New Virtual Machine.
    2. Select a name and a folder for your VM.
    3. Select a computer resource: choose a destination computer resource for this operation.
    4. Select storage: For example, select NFS-Node1
    5. Select compatibility: The image should be BIOS only.
    6. Select a guest operating system: For example, select Linux and Red Hat Fedora (64-bit).
    7. Customize hardware: When creating a VM, on the Device Configuration button on the upper right, delete the default New Hard Disk and use the drop-down to select an Existing Hard Disk disk image:
    8. Ready to complete: Review the details and click Finish to create the image.
  6. Navigate to the VMs tab.

    1. From the list, select the VM you created.
    2. Click the Start button from the panel. A new window appears, showing the VM image loading.
    3. Log in with the credentials you created for the blueprint.
    4. You can verify if the packages you added to the blueprint are installed. For example:

      $ rpm -qa | grep firefox

10.11. Pushing customized images to OCI

With RHEL image builder, you can build customized images and push them directly to your Oracle Cloud Infrastructure (OCI) instance. Then, you can start an image instance from the OCI dashboard.

Prerequisites

  • You have root or weldr group user access to the system.
  • You have an Oracle Cloud account.
  • You must be granted security access in an OCI policy by your administrator.
  • You have created an OCI Bucket in the OCI_REGION of your choice.

Procedure

  1. Open the RHEL image builder interface of the web console in a browser.
  2. Click Create blueprint. The Create blueprint wizard opens.
  3. On the Details page, enter a name for the blueprint, and optionally, a description. Click Next.
  4. On the Packages page, select the components and packages that you want to include in the image. Click Next.
  5. On the Customizations page, configure the customizations that you want for your blueprint. Click Next.
  6. On the Review page, click Create.
  7. To create an image, click Create Image. The Create image wizard opens.
  8. On the Image output page, complete the following steps:

    1. From the "Select a blueprint" drop-down menu, select the blueprint you want.
    2. From the "Image output type" drop-down menu, select Oracle Cloud Infrastructure (.qcow2).
    3. Check the "Upload OCI checkbox to upload your image to the OCI.
    4. Enter the "image size". Click Next.
  9. On the Upload to OCI - Authentication page, enter the following mandatory details:

    1. User OCID: you can find it in the Console on the page showing the user’s details.
    2. Private key
  10. On the Upload to OCI - Destination page, enter the following mandatory details and click Next.

    1. Image name: a name for the image to be uploaded.
    2. OCI bucket
    3. Bucket namespace
    4. Bucket region
    5. Bucket compartment
    6. Bucket tenancy
  11. Review the details in the wizard and click Finish.

RHEL image builder adds the compose of a RHEL .qcow2 image to the queue.

Verification

  1. Access the OCI dashboard → Custom Images.
  2. Select the Compartment you specified for the image and locate the image in the Import image table.
  3. Click the image name and verify the image information.

10.12. Uploading QCOW2 images to OpenStack

With the RHEL image builder tool, you can create customized .qcow2 images that are suitable for uploading to OpenStack cloud deployments, and starting instances there. RHEL image builder creates images in the QCOW2 format, but with further changes specific to OpenStack.

Warning

Do not mistake the generic QCOW2 image type output format you create by using RHEL image builder with the OpenStack image type, which is also in the QCOW2 format, but contains further changes specific to OpenStack.

Prerequisites

  • You have created a blueprint.

Procedure

  1. Start the compose of a QCOW2 image.

    # composer-cli compose start blueprint_name openstack
  2. Check the status of the building.

    # composer-cli compose status

    After the image build finishes, you can download the image.

  3. Download the QCOW2 image:

    # composer-cli compose image UUID
  4. Access the OpenStack dashboard and click +Create Image.
  5. On the left menu, select the Admin tab.
  6. From the System Panel, click Image.

    The Create An Image wizard opens.

  7. In the Create An Image wizard:

    1. Enter a name for the image
    2. Click Browse to upload the QCOW2 image.
    3. From the Format dropdown list, select the QCOW2 - QEMU Emulator.
    4. Click Create Image.

      composer openstack upload image

  8. On the left menu, select the Project tab.

    1. From the Compute menu, select Instances.
    2. Click the Launch Instance button.

      The Launch Instance wizard opens.

    3. On the Details page, enter a name for the instance. Click Next.
    4. On the Source page, select the name of the image you uploaded. Click Next.
    5. On the Flavor page, select the machine resources that best fit your needs. Click Launch.

      composer openstack start instance

  9. You can run the image instance using any mechanism (CLI or OpenStack web UI) from the image. Use your private key via SSH to access the resulting instance. Log in as cloud-user.

10.13. Preparing to upload customized RHEL images to Alibaba Cloud

To deploy a customized RHEL image to the Alibaba Cloud, first you need to verify the customized image. The image needs a specific configuration to boot successfully, because Alibaba Cloud requests the custom images to meet certain requirements before you use it.

Note

RHEL image builder generates images that conform to Alibaba’s requirements. However, Red Hat recommends also using the Alibaba image_check tool to verify the format compliance of your image.

Prerequisites

  • You must have created an Alibaba image by using RHEL image builder.

Procedure

  1. Connect to the system containing the image that you want to check by using the Alibaba image_check tool.
  2. Download the image_check tool:

    $ curl -O https://docs-aliyun.cn-hangzhou.oss.aliyun-inc.com/assets/attach/73848/cn_zh/1557459863884/image_check
  3. Change the file permission of the image compliance tool:

    # chmod +x image_check
  4. Run the command to start the image compliance tool checkup:

    # ./image_check

    The tool verifies the system configuration and generates a report that is displayed on your screen. The image_check tool saves this report in the same folder where the image compliance tool is running.

Troubleshooting

If any of the Detection Items fail, follow the instructions in the terminal to correct it.

Additional resources

10.14. Uploading customized RHEL images to Alibaba

You can upload a customized AMI image you created by using RHEL image builder to the Object Storage Service (OSS).

Prerequisites

Procedure

  1. Log in to the OSS console.
  2. In the Bucket menu on the left, select the bucket to which you want to upload an image.
  3. In the upper right menu, click the Files tab.
  4. Click Upload. A dialog window opens on the right side. Configure the following:

    • Upload To: Choose to upload the file to the Current directory or to a Specified directory.
    • File ACL: Choose the type of permission of the uploaded file.
  5. Click Upload.
  6. Select the image you want to upload to the OSS Console..
  7. Click Open.

10.15. Importing images to Alibaba Cloud

To import a customized Alibaba RHEL image that you created by using RHEL image builder to the Elastic Compute Service (ECS), follow the steps:

Prerequisites

Procedure

  1. Log in to the ECS console.

    1. On the left-side menu, click Images.
    2. On the upper right side, click Import Image. A dialog window opens.
    3. Confirm that you have set up the correct region where the image is located. Enter the following information:

      1. OSS Object Address: See how to obtain OSS Object Address.
      2. Image Name
      3. Operating System
      4. System Disk Size
      5. System Architecture
      6. Platform: Red Hat
    4. Optionally, provide the following details:

      1. Image Format: qcow2 or ami, depending on the uploaded image format.
      2. Image Description
      3. Add Images of Data Disks

        The address can be determined in the OSS management console. After selecting the required bucket in the left menu:

  2. Select Files section.
  3. Click the Details link on the right for the appropriate image.

    A window appears on the right side of the screen, showing image details. The OSS object address is in the URL box.

  4. Click OK.

    Note

    The importing process time can vary depending on the image size.

The customized image is imported to the ECS Console.

10.16. Creating an instance of a customized RHEL image using Alibaba Cloud

You can create instances of a customized RHEL image by using the Alibaba ECS Console.

Prerequisites

Procedure

  1. Log in to the ECS console.
  2. On the left-side menu, select Instances.
  3. In the upper-right corner, click Create Instance. You are redirected to a new window.
  4. Complete all the required information. See Creating an instance by using the wizard for more details.
  5. Click Create Instance and confirm the order.

    Note

    You can see the option Create Order instead of Create Instance, depending on your subscription.

As a result, you have an active instance ready for deployment from the Alibaba ECS Console.

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