Customizing Anaconda
Changing the installer appearance and creating custom add-ons on Red Hat Enterprise Linux 8
Abstract
Making open source more inclusive
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Chapter 1. Introduction to Anaconda customization
1.1. Introduction to Anaconda Customization
The Red Hat Enterprise Linux and Fedora installation program, Anaconda, brings many improvements in its most recent versions. One of these improvements is enhanced customizability. You can now write add-ons to extend the base installer functionality, and change the appearance of the graphical user interface.
This document will explain how to customize the following:
- Boot menu - pre-configured options, color scheme and background
- Appearance of the graphical interface - logo, backgrounds, product name
- Installer functionality - add-ons which can enhance the installer by adding new Kickstart commands and new screens in the graphical and textual user interfaces
Also note that this document applies only to Red Hat Enterprise Linux 8 and Fedora 17 and later.
Procedures described in this book are written for Red Hat Enterprise Linux 8 or a similar system. On other systems, the tools and applications used (such as genisoimage
for creating custom ISO images) may be different, and procedures may need to be adjusted.
1.2. Performing the pre-customization tasks
1.2.1. Working with ISO images
In this section, you will learn how to:
- Extract a Red Hat ISO.
- Create a new boot image containing your customizations.
1.2.2. Downloading RH boot images
Before you begin to customize the installer, download the Red Hat-provided boot images. You can obtain Red Hat Enterprise Linux 8 boot media from the Red Hat Customer Portal after login to your account.
- Your account must have sufficient entitlements to download Red Hat Enterprise Linux 8 images.
-
You must download either the
Binary DVD
orBoot ISO
image and can use any of the image variants (Server or ComputeNode). -
You cannot customize the installer using the other available downloads, such as the KVM Guest Image or Supplementary DVD; other available downloads, such as the
KVM Guest Image
orSupplementary DVD
.
For more information about the Binary DVD and Boot ISO downloads, see the Red Hat Enterprise Linux 8 Performing an Advanced RHEL Installation.
1.2.3. Extracting Red Hat Enterprise Linux boot images
Perform the following procedure to extract the contents of a boot image.
Procedure
-
Ensure that the directory
/mnt/iso
exists and nothing is currently mounted there. Mount the downloaded image.
# mount -t iso9660 -o loop path/to/image.iso /mnt/iso
Where path/to/image.iso is the path to the downloaded boot image.
Create a working directory where you want to place the contents of the ISO image.
$
mkdir /tmp/ISO
Copy all contents of the mounted image to your new working directory. Make sure to use the
-p
option to preserve file and directory permissions and ownership.#
cp -pRf /mnt/iso /tmp/ISOUnmount the image.
#
umount /mnt/iso
Additional resources
- For detailed download instructions and description of the Binary DVD and Boot ISO downloads, see the Red Hat Enterprise Linux 8 .
Chapter 3. Branding and chroming the graphical user interface
The customization of Anaconda user interface may include the customization of graphical elements and the customization of product name.
This section provides information about how to customize the graphical elements and the product name.
Prerequisites
- You have downloaded and extracted the ISO image.
- You have created your own branding material.
For information about downloading and extracting boot images, see Section 1.2.3, “Extracting Red Hat Enterprise Linux boot images”
The user interface customization involves the following high-level tasks:
- Complete the prerequisites.
- Create custom branding material (if you plan to customize the graphical elements)
- Customize the graphical elements (if you plan to customize it)
- Customize the product name (if you plan to customize it)
- Create a product.img file
- Create a custom Boot image
To create the custom branding material, first refer to the default graphical element files type and dimensions. You can accordingly create the custom material. Details about default graphical elements are available in the sample files that are provided in the Section 3.1, “Customizing graphical elements” section.
3.1. Customizing graphical elements
To customize the graphical elements, you can modify or replace the customisable elements with the custom branded material, and update the container files.
The customisable graphical elements of the installer are stored in the /usr/share/anaconda/pixmaps/
directory in the installer runtime file system. This directory contains the following customisable files:
pixmaps ├─ anaconda-password-show-off.svg ├─ anaconda-password-show-on.svg ├─ right-arrow-icon.png ├─ sidebar-bg.png ├─ sidebar-logo.png └─ topbar-bg.png
Additionally, the /usr/share/anaconda/
directory contains a CSS stylesheet named anaconda-gtk.css
, which determines the file names and parameters of the main UI elements - the logo and the backgrounds for the sidebar and top bar. The file has the following contents that can be customized as per your requirement:
/* theme colors/images */ @define-color product_bg_color @redhat; /* logo and sidebar classes */ .logo-sidebar { background-image: url('/usr/share/anaconda/pixmaps/sidebar-bg.png'); background-color: @product_bg_color; background-repeat: no-repeat; } /* Add a logo to the sidebar */ .logo { background-image: url('/usr/share/anaconda/pixmaps/sidebar-logo.png'); background-position: 50% 20px; background-repeat: no-repeat; background-color: transparent; } /* This is a placeholder to be filled by a product-specific logo. */ .product-logo { background-image: none; background-color: transparent; } AnacondaSpokeWindow #nav-box { background-color: @product_bg_color; background-image: url('/usr/share/anaconda/pixmaps/topbar-bg.png'); background-repeat: no-repeat; color: white; }
The most important part of the CSS file is the way in which it handles scaling based on resolution. The PNG image backgrounds do not scale, they are always displayed in their true dimensions. Instead, the backgrounds have a transparent background, and the stylesheet defines a matching background color on the @define-color
line. Therefore, the background images "fade" into the background color, which means that the backgrounds work on all resolutions without a need for image scaling.
You could also change the background-repeat
parameters to tile the background, or, if you are confident that every system you will be installing on will have the same display resolution, you can use background images which fill the entire bar.
Any of the files listed above can be customized. Once you do so, follow the instructions in Section 2.2, “Creating a product.img File” to create your own product.img with custom graphics, and then Section 2.3, “Creating Custom Boot Images” to create a new bootable ISO image with your changes included.
3.2. Customizing the product name
To customize the product name, you must create a custom .buildstamp file
. To do so, create a new file .buildstamp.py
with the following content:
[Main] Product=My Distribution Version=8.3 BugURL=https://bugzilla.redhat.com/ IsFinal=True UUID=202007011344.x86_64 [Compose] Lorax=28.14.49-1
Change My Distribution to the name which you want to display in the installer.
After you create the custom .buildstamp file, follow the steps in Section 5.1, “Creating a product img file” section to create a new product.img file containing your customizations, and the Section 5.2, “Creating custom boot images” section to create a new bootable ISO file with your changes included.
3.3. Customizing the Default Configuration
You can create your own configuration file and use it to customize the configuration of the installer.
3.3.1. Configuring the default configuration files
You can write the Anaconda configuration files in the .ini
file format. The Anaconda configuration file consists of sections, options and comments. Each section is defined by a [section]
header, the comments starting with a #
character and the keys to define the options
. The resulting configuration file is processed with the configparser
configuration file parser.
The default configuration file, located at /etc/anaconda/anaconda.conf
, contains the documented sections and options that are supported. The file provides a full default configuration of the installer. You can modify the configuration of the product configuration files from /etc/anaconda/product.d/
and the custom configuration files from /etc/anaconda/conf.d/
.
The following configuration file describes the default configuration of RHEL 8.3:
[Anaconda] # Run Anaconda in the debugging mode. debug = False # Enable Anaconda addons. addons_enabled = True # List of enabled Anaconda DBus modules. kickstart_modules = org.fedoraproject.Anaconda.Modules.Timezone org.fedoraproject.Anaconda.Modules.Network org.fedoraproject.Anaconda.Modules.Localization org.fedoraproject.Anaconda.Modules.Security org.fedoraproject.Anaconda.Modules.Users org.fedoraproject.Anaconda.Modules.Payloads org.fedoraproject.Anaconda.Modules.Storage org.fedoraproject.Anaconda.Modules.Services org.fedoraproject.Anaconda.Modules.Subscription [Installation System] # Should the installer show a warning about enabled SMT? can_detect_enabled_smt = True [Installation Target] # Type of the installation target. type = HARDWARE # A path to the physical root of the target. physical_root = /mnt/sysimage # A path to the system root of the target. system_root = /mnt/sysroot [Network] # Network device to be activated on boot if none was configured so. # Valid values: # # NONE No device # DEFAULT_ROUTE_DEVICE A default route device # FIRST_WIRED_WITH_LINK The first wired device with link # default_on_boot = DEFAULT_ROUTE_DEVICE [Payload] # Default package environment. default_environment = # List of ignored packages. ignored_packages = ntfsprogs btrfs-progs dmraid # Enable installation of latest updates. enable_updates = False # List of .treeinfo variant types to enable. # Valid items: # # addon # optional # variant # enabled_repositories_from_treeinfo = addon optional variant # Enable installation from the closest mirror. enable_closest_mirror = False # Default installation source. # Valid values: # # CLOSEST_MIRROR Use closest public repository mirror. # CDN Use Content Delivery Network (CDN). # default_source = CDN # Enable ssl verification for all HTTP connection verify_ssl = True [Security] # Enable SELinux usage in the installed system. # Valid values: # # -1 The value is not set. # 0 SELinux is disabled. # 1 SELinux is enabled. # selinux = -1 [Bootloader] # Type of the bootloader. # Supported values: # # DEFAULT Choose the type by platform. # EXTLINUX Use extlinux as the bootloader. # type = DEFAULT # Name of the EFI directory. efi_dir = redhat # Hide the GRUB menu. menu_auto_hide = False # Are non-iBFT iSCSI disks allowed? nonibft_iscsi_boot = False # Arguments preserved from the installation system. preserved_arguments = cio_ignore rd.znet rd_ZNET zfcp.allow_lun_scan speakup_synth apic noapic apm ide noht acpi video pci nodmraid nompath nomodeset noiswmd fips selinux biosdevname ipv6.disable net.ifnames net.ifnames.prefix nosmt [Storage] # Enable dmraid usage during the installation. dmraid = True # Enable iBFT usage during the installation. ibft = True # Do you prefer creation of GPT disk labels? gpt = False # Tell multipathd to use user friendly names when naming devices during the installation. multipath_friendly_names = True # Do you want to allow imperfect devices (for example, degraded mdraid array devices)? allow_imperfect_devices = False # Default file system type. Use whatever Blivet uses by default. file_system_type = xfs # Default partitioning. # Valid values: # # SERVER Choose partitioning for servers. # WORKSTATION Choose partitioning for workstations. # VIRTUALIZATION Choose partitioning for virtualizations. # default_partitioning = WORKSTATION # Default partitioning scheme. # Valid values: # # PLAIN Create standard partitions. # BTRFS Use the Btrfs scheme. # LVM Use the LVM scheme. # LVM_THINP Use LVM Thin Provisioning. # default_scheme = LVM # Default version of LUKS. # Valid values: # # luks1 Use version 1 by default. # luks2 Use version 2 by default. # luks_version = luks2 [Storage Constraints] # Minimal size of the total memory. min_ram = 320 MiB # Minimal size of the available memory for LUKS2. luks2_min_ram = 128 MiB # Should we recommend specifying a swap partition? swap_is_recommended = True # Recommended minimal sizes of partitions. # Specify a mount point and a size on each line. min_partition_sizes = / 250 MiB /usr 250 MiB /tmp 50 MiB /var 384 MiB /home 100 MiB /boot 200 MiB # Required minimum sizes of partitions. # Specify a mount point and a size on each line. req_partition_sizes = # Allowed device types of the / partition if any. # Valid values: # # LVM Allow LVM. # MD Allow RAID. # PARTITION Allow standard partitions. # BTRFS Allow Btrfs. # DISK Allow disks. # LVM_THINP Allow LVM Thin Provisioning. # root_device_types = # Mount points that must be on a linux file system. # Specify a list of mount points. must_be_on_linuxfs = / /var /tmp /usr /home /usr/share /usr/lib # Paths that must be directories on the / file system. # Specify a list of paths. must_be_on_root = /bin /dev /sbin /etc /lib /root /mnt lost+found /proc # Paths that must NOT be directories on the / file system. # Specify a list of paths. must_not_be_on_root = [User Interface] # The path to a custom stylesheet. custom_stylesheet = # The path to a directory with help files. help_directory = /usr/share/anaconda/help/rhel # Default help pages for TUI, GUI and Live OS. default_help_pages = rhel_help_placeholder.txt rhel_help_placeholder.xml rhel_help_placeholder.xml # A list of spokes to hide in UI. # FIXME: Use other identification then names of the spokes. hidden_spokes = [License] # A path to EULA (if any) # # If the given distribution has an EULA & feels the need to # tell the user about it fill in this variable by a path # pointing to a file with the EULA on the installed system. # # This is currently used just to show the path to the file to # the user at the end of the installation. eula = /usr/share/redhat-release/EULA
3.3.2. Configuring the product configuration files
The product configuration files have one or two extra sections that identify the product. The [Product]
section specifies the product name of a product. The [Base Product]
section specifies the product name of a base product if any. For example, Red Hat Enterprise Linux is a base product of Red Hat Virtualization.
The installer loads configuration files of the base products before it loads the configuration file of the specified product. For example, it will first load the configuration for Red Hat Enterprise Linux and then the configuration for Red Hat Virtualization.
See an example of the product configuration file for Red Hat Virtualization:
[Product] product_name = Red Hat Virtualization [Base Product] product_name = Red Hat Enterprise Linux [Storage] default_scheme = LVM_THINP default_partitioning = VIRTUALIZATION [Storage Constraints] root_device_types = LVM_THINP must_not_be_on_root = /var req_partition_sizes = /var 10 GiB /boot 1 GiB [User Interface] help_directory = /usr/share/anaconda/help/rhv
To customize the installer configuration for your product, you must create a product configuration file. Create a new file named my-distribution.conf
, with content similar to the example above. Change product_name in the [Product]
section to the name of your product, for example My Distribution. The product name should be the same as the name used in the .buildstamp
file.
After you create the custom configuration file, follow the steps in Section 5.1, “Creating a product img file” section to create a new product.img
file containing your customizations, and the Section 5.2, “Creating custom boot images” to create a new bootable ISO file with your changes included.
3.3.3. Configuring the custom configuration files
To customize the installer configuration independently of the product name, you must create a custom configuration file. To do so, create a new file named 100-my-configuration.conf
with the content similar to the example in Section 3.3.2, “Configuring the product configuration files” and omit the [Product]
and [Base Product]
sections.
After you create the custom configuration file, follow the steps in Section 5.1, “Creating a product img file” section to create a new product.img
file containing your customizations, and the Section 5.2, “Creating custom boot images” to create a new bootable ISO file with your changes included.
Chapter 4. Developing installer add-ons
This section provides details about Anaconda and it’s architecture, and how to develop your own add-ons. The details about Anaconda and its architecture helps you to understand Anaconda backend and various plug points for the add-ons to work. It also helps to accordingly develop the add-ons.
4.1. Introduction to Anaconda and add-ons
Anaconda is the operating system installer used in Fedora, Red Hat Enterprise Linux, and their derivatives. It is a set of Python modules and scripts together with some additional files like Gtk
widgets (written in C), systemd
units, and dracut
libraries. Together, they form a tool that allows users to set parameters of the resulting (target) system and then set up this system on a machine. The installation process has four major steps:
- Prepare installation destination (usually disk partitioning)
- Install package and data
- Install and configure boot loader
- Configure newly installed system
Using Anaconda enables you to install Fedora, Red Hat Enterprise Linux, and their derivatives, in the following three ways:
Using graphical user interface (GUI):
This is the most common installation method. The interface allows users to install the system interactively with little or no configuration required before starting the installation. This method covers all common use cases, including setting up complicated partitioning layouts.
The graphical interface supports remote access over VNC
, which allows you to use the GUI even on systems with no graphics cards or attached monitor.
Using text user interface (TUI):
The TUI works similar to a monochrome line printer, which allows it to work on serial consoles that do not support cursor movement, colors and other advanced features. The text mode is limited and allows you to customize only the most common options, such as network settings, language options or installation (package) source; advanced features such as manual partitioning are not available in this interface.
Using Kickstart file:
A Kickstart file is a plain text file with shell-like syntax that can contain data to drive the installation process. A Kickstart file allows you to partially or completely automate the installation. A set of commands which configures all required areas is necessary to completely automate the installation. If one or more commands are missed, the installation requires interaction.
Apart from automation of the installer itself, Kickstart files can contain custom scripts that are run at specific moments during the installation process.
4.2. Anaconda Architecture
Anaconda is a set of Python modules and scripts. It also uses several external packages and libraries. The major components of this toolset include the following packages:
-
pykickstart
- parses and validates the Kickstart files. Also, provides data structure that stores values that drives the installation. -
yum
- the package manager that installs packages and resolves dependencies -
blivet
- handles all activities related to storage management -
pyanaconda
- contains the user interface and modules for Anaconda, such as keyboard and timezone selection, network configuration, and user creation. Also provides various utilities to perform system-oriented functions -
python-meh
- contains an exception handler that gathers and stores additional system information in case of a crash and passes this information to thelibreport
library, which itself is a part of the ABRT Project -
dasbus
- enables communication between theD-Bus
library with modules of anaconda and with external components -
python-simpleline
- text UI framework library to manage user interaction in the Anaconda text mode -
gtk
- the Gnome toolkit library for creating and managing GUI
Apart from the division into packages previously mentioned, Anaconda is internally divided into the user interface and a set of modules that run as separate processes and communicate using the D-Bus
library. These modules are:
-
Boss
- manages the internal module discovery, lifecycle, and coordination -
Localization
- manages locales -
Network
- handles network -
Payloads
- handles data for installation in different formats, such asrpm
,ostree
,tar
and other installation formats. Payloads manage the sources of data for installation; sources can vary in format such as CD-ROM, HDD, NFS, URLs, and other sources -
Security
- manages security related aspects -
Services
- handles services -
Storage
- manages storage usingblivet
-
Subscription
- handles thesubscription-manager
tool and Insights. -
Timezone
- deals with time, date, zones, and time synchronization. -
Users
- creates users and groups.
Each module declares which parts of Kickstart it handles, and has methods to apply the configuration from Kickstart to the installation environment and to the installed system.
The Python code portion of Anaconda (pyanaconda
) starts as a “main” process that owns the user interface. Any Kickstart data you provide are parsed using the pykickstart
module and the Boss
module is started, it discovers all other modules, and starts them. Main process then sends Kickstart data to the modules according to their declared capabilities. Modules process the data, apply the configuration to the installation environment, and the UI validates if all required choices have been made. If not, you must supply the data in an interactive installation mode. Once all required choices have been made, the installation can start - the modules write data to the installed system.
4.3. Anaconda User Interface
The Anaconda user interface (UI) has a non-linear structure, also known as hub and spoke model.
The advantages of Anaconda hub and spoke model are:
- Flexibility to follow the installer screens.
- Flexibility to retain the default settings.
- Provides an overview of the configured values.
- Supports extensibility. You can add hubs without the need to reorder anything and can resolve some complex ordering dependencies.
- Supports installation in graphical and text mode.
The following diagram shows the installer layout and the possible interactions between hubs and spokes (screens):
Figure 4.1. Hub and spoke model

In the diagram, screens 2-13 are called normal spokes, and screens 1 and 14 are standalone spokes. Standalone spokes are the screens that can be used before or after the standalone spoke or hub. For example, the Welcome
screen at the beginning of the installation which prompts you to choose your language for the rest of the installation.
-
The
Installation Summary
is the only hub in Anaconda. It shows a summary of configured options before the installation begins
Each spoke has the following predefined properties that reflect the hub.
-
ready
- states whether or not you can visit a spoke. For example, when the installer is configuring a package source, the spoke is colored in gray, and you cannot access it until the configuration is complete. -
completed
- marks whether or not is the spoke complete (all required values are set). -
mandatory
- determines whether you must visit the spoke before continuing the installation; for example, you must visit theInstallation Destination
spoke, even if you want to use automatic disk partitioning -
status
- provides a short summary of values configured within the spoke (displayed under the spoke name in the hub)
To make the user interface clearer, spokes are grouped together into categories. For example, the Localization
category groups together spokes for keyboard layout selection, language support and time zone settings.
Each spoke contains UI controls which display and allow you to modify values from one or more modules. The same applies to spokes that add-ons provide.
4.4. Communication across Anaconda threads
Some of the actions that you need to perform during the installation process may take a long time. For example, scanning disks for existing partitions or downloading package metadata. To prevent you from waiting and remaining responsive, Anaconda runs these actions in separate threads.
The Gtk toolkit does not support element changes from multiple threads. The main event loop of Gtk runs in the main thread of the Anaconda process. Therefore, all actions pertaining to the GUI must be performed in the main thread. To do so, use GLib.idle_add
, which is not always easy or desired. Several helper functions and decorators that are defined in the pyanaconda.ui.gui.utils module may add to the difficulty.
The @gtk_action_wait
and @gtk_action_nowait
decorators change the decorated function or method in such a way that when this function or method is called, it is automatically queued into Gtk’s main loop that runs in the main thread. The return value is either returned to the caller or dropped, respectively.
In a spoke and hub communication, a spoke announces when it is ready and is not blocked. The hubQ
message queue handles this function, and periodically checks the main event loop. When a spoke becomes accessible, it sends a message to the queue announcing the change and that it should no longer be blocked.
The same applies in a situation where a spoke needs to refresh its status or complete a flag. The Configuration and Progress
hub has a different queue called progressQ
which serves as a medium to transfer installation progress updates.
These mechanisms are also used for the text-based interface. In the text mode, there is no main loop, but the keyboard input takes most of the time.
4.5. Anaconda Modules and D-Bus library
Anaconda’s modules run as independent processes. To communicate with these processes via their D-Bus
API, use the dasbus
library.
Calls to methods via D-Bus`API are asynchronous, but with the `dasbus
library you can convert them to synchronous method calls in Python. You can also write either of the following programs:
- program with asynchronous calls and return handlers
- A program with synchronous calls that makes the caller wait until the call is complete.
For more information about threads and communication, see Section 4.4, “Communication across Anaconda threads”.
Additionally, Anaconda uses Task objects running in modules. Tasks have a D-Bus
API and methods that are automatically executed in additional threads. To successfully run the tasks, use the sync_run_task
and async_run_task
helper functions.
4.6. The Hello World addon example
Anaconda developers publish an example addon called “Hello World”, available on GitHub: https://github.com/rhinstaller/hello-world-anaconda-addon/ The descriptions in further sections are reproduced in this.
4.7. Anaconda add-on structure
An Anaconda add-on is a Python package that contains a directory with an __init__.py
and other source directories (subpackages). Because Python allows you to import each package name only once, specify a unique name for the package top-level directory. You can use an arbitrary name, because add-ons are loaded regardless of their name - the only requirement is that they must be placed in a specific directory.
The suggested naming convention for add-ons is similar to Java packages or D-Bus service names.
To make the directory name a unique identifier for a Python package, prefix the add-on name with the reversed domain name of your organization, using underscores (_
) instead of dots. For example, com_example_hello_world
.
Make sure to create an __init__.py
file in each directory. Directories missing this file are considered as invalid Python packages.
When writing an add-on, ensure the following:
-
Support for each interface (graphical interface and text interface) is available in a separate subpackage and these subpackages are named
gui
for the graphical interface andtui
for the text-based interface. -
The
gui
andtui
packages contain aspokes
subpackage. [1] - Modules contained in the packages have an arbitrary name.
-
The
gui/
andtui/
directories contain Python modules with any name. - There is a service that performs the actual work of the addon. This service can be written in Python or any other language.
- The service implements support for D-Bus and Kickstart.
- The addon contains files that enable automatic startup of the service.
Following is a sample directory structure for an add-on which supports every interface (Kickstart, GUI and TUI):
Example 4.1. Sample Add-on Structure
com_example_hello_world ├─ gui │ ├─ init.py │ └─ spokes │ └─ init.py └─ tui ├─ init.py └─ spokes └─ init.py
Each package must contain at least one module with an arbitrary name defining the classes that are inherited from one or more classes defined in the API.
For all add-ons, follow Python’s PEP 8 and PEP 257 guidelines for docstring conventions. There is no consensus on the format of the actual content of docstrings in Anaconda; the only requirement is that they are human-readable. If you plan to use auto-generated documentation for your add-on, docstrings should follow the guidelines for the toolkit you use to accomplish this.
You can include a category subpackage if an add-on needs to define a new category, but this is not recommended.
4.8. Anaconda services and configuration files
Anaconda services and configuration files are included in data/ directory. These files are required to start the add-ons service and to configure D-Bus.
Following are some examples of Anaconda Hello World add-on:
Example 4.2. Example of addon-name.conf:
<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN" "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd"> <busconfig> <policy user="root"> <allow own="org.fedoraproject.Anaconda.Addons.HelloWorld"/> <allow send_destination="org.fedoraproject.Anaconda.Addons.HelloWorld"/> </policy> <policy context="default"> <deny own="org.fedoraproject.Anaconda.Addons.HelloWorld"/> <allow send_destination="org.fedoraproject.Anaconda.Addons.HelloWorld"/> </policy> </busconfig>
This file must be placed in the /usr/share/anaconda/dbus/confs/
directory in the installation environment. The string org.fedoraproject.Anaconda.Addons.HelloWorld
must correspond to the location of addon’s service on D-Bus.
Example 4.3. Example of addon-name.service:
[D-BUS Service]
# Start the org.fedoraproject.Anaconda.Addons.HelloWorld service.
# Runs org_fedora_hello_world/service/main.py
Name=org.fedoraproject.Anaconda.Addons.HelloWorld
Exec=/usr/libexec/anaconda/start-module org_fedora_hello_world.service
User=root
This file must be placed in the /usr/share/anaconda/dbus/services/
directory in the installation environment. The string org.fedoraproject.Anaconda.Addons.HelloWorld
must correspond to the location of addon’s service on D-Bus. The value on the line starting with Exec=
must be a valid command that starts the service in the installation environment.
4.9. Deploying and testing an Anaconda add-on
You can deploy and test your own Anaconda add-on into the installation environment. To do so, follow the steps:
Prerequisites
- You created an Add-on.
-
You have access to your
D-Bus
files.
Procedure
-
Create a directory
DIR
at the place of your preference. -
Add the
Add-on
python files intoDIR/usr/share/anaconda/addons/
. -
Copy your
D-Bus
service file intoDIR/usr/share/anaconda/dbus/services/
. -
Copy your
D-Bus
service configuration file to/usr/share/anaconda/dbus/confs/
. Create the updates image.
Access the
DIR
directory:cd DIR
Locate the updates image.
find . | cpio -c -o | pigz -9cv > DIR/updates.img
- Extract the contents of the ISO boot image.
Use the resulting
updates
image:-
Add the
updates.img
file into the images directory of your unpacked ISO contents. - Repack the image.
-
Set up a web server to provide the
updates
.img file to the Anaconda installer via HTTP. Load
updates
.img file at boot time by adding the following specification to the boot options.inst.updates=http://your-server/whatever/updates.img to boot options.
-
Add the
For specific instructions on unpacking an existing boot image, creating a product.img
file and repackaging the image, see Section 1.2.3, “Extracting Red Hat Enterprise Linux boot images”.
Chapter 5. Completing post customization tasks
To complete the customizations made, perform the following tasks:
- Create a product.img image file (applies only for graphical customizations).
- Create a custom boot image.
This section provides information about how to create a product.img image file and to create a custom boot image.
5.1. Creating a product img file
A product.img
image file is an archive containing new installer files that replace the existing ones at runtime.
During a system boot, Anaconda loads the product.img file from the images/ directory on the boot media. It then uses the files that are present in this directory to replace identically named files in the installer’s file system. The files when replaced customizes the installer (for example, for replacing default images with custom ones).
Note: The product.img
image must contain a directory structure identical to the installer. For more information about the installer directory structure, see table, Table 5.1, “Installer directory structure and custom contents”
Table 5.1. Installer directory structure and custom contents
Type of custom content | File system location |
---|---|
Pixmaps (logo, sidebar, top bar, and so on.) |
|
GUI stylesheet |
|
Anaconda add-ons |
|
Product configuration files |
|
Custom configuration files |
|
Anaconda DBus service conf files |
|
Anaconda DBus service files |
|
The procedure below explains how to create a product.img
file.
Procedure
Navigate to a working directory such as
/tmp
, and create a subdirectory namedproduct/
:$
cd /tmp
Create a subdirectory product/
$
mkdir product/
Create a directory structure identical to the location of the file you want to replace. For example, if you want to test an add-on that is present in the
/usr/share/anaconda/addons
directory on the installation system, create the same structure in your working directory:$
mkdir -p product/usr/share/anaconda/addons
NoteTo view the installer’s runtime file, boot the installation and switch to virtual console 1 (Ctrl+Alt+F1) and then switch to the second tmux window (Ctrl+b 2). A shell prompt that can be used to browse a file system opens.
Place your customized files (in this example, custom add-on for Anaconda) into the newly created directory:
$
cp -r ~/path/to/custom/addon/ product/usr/share/anaconda/addons/
- Repeat steps 3 and 4 (create a directory structure and place the custom files into it) for every file you want to add to the installer.
Create a
.buildstamp
file in the root of the directory. The.buildstamp
file describes the system version, the product and several other parameters. The following is an example of a.buildstamp
file from Red Hat Enterprise Linux 8.3:[Main] Product=Red Hat Enterprise Linux Version=8.3 BugURL=https://bugzilla.redhat.com/ IsFinal=True UUID=202007011344.x86_64 [Compose] Lorax=28.14.49-1
The
IsFinal
parameter, specifies whether the image is for a release (GA) version of the product (True
), or a pre-release such as Alpha, Beta, or an internal milestone (False
).Navigate to the
product/
directory, and create theproduct.img
archive:$
cd product
$
find . | cpio -c -o | gzip -9cv > ../product.img
This creates a
product.img
file one level above theproduct/
directory.-
Move the
product.img
file to theimages/
directory of the extracted ISO image.
The product.img file is now created and the customizations that you want to make are placed in the respective directories.
Instead of adding the product.img
file on the boot media, you can place this file into a different location and use the inst.updates=
boot option at the boot menu to load it. In that case, the image file can have any name, and it can be placed in any location (USB flash drive, hard disk, HTTP, FTP or NFS server), as long as this location is reachable from the installation system.
See the Anaconda Boot Options for more information about Anaconda boot options.
5.2. Creating custom boot images
After you customize the boot images and the GUI layout, create a new image that includes the changes you made.
To create custom boot images, follow the procedure below.
Procedure
-
Make sure that all of your changes are included in the working directory. For example, if you are testing an add-on, make sure to place the
product.img
in theimages/
directory. -
Make sure your current working directory is the top-level directory of the extracted ISO image - e.g.
/tmp/ISO/iso
. Create a new ISO image using the
genisoimage
:#
genisoimage -U -r -v -T -J -joliet-long -V "RHEL-8.2 Server.x86_64" -volset "RHEL-8.2 Server.x86_64" -A "RHEL-8.2 Server.x86_64" -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -eltorito-alt-boot -e images/efiboot.img -no-emul-boot -o ../NEWISO.iso .In the above example:
Make sure that the values for
-V
,-volset
, and-A
options match the image’s boot loader configuration, if you are using theLABEL=
directive for options that require a location to load a file on the same disk. If your boot loader configuration (isolinux/isolinux.cfg
for BIOS andEFI/BOOT/grub.cfg
for UEFI) uses theinst.stage2=LABEL=disk_label
stanza to load the second stage of the installer from the same disk, then the disk labels must match.ImportantIn boot loader configuration files, replace all spaces in disk labels with
\x20
. For example, if you create an ISO image with aRHEL 8.2
label, boot loader configuration should useRHEL\x207.1
.Replace the value of the
-o
option (-o ../NEWISO.iso
) with the file name of your new image. The value in the example creates theNEWISO.iso
file in the directory above the current one.For more information about this command, see the
genisoimage(1)
man page.
Implant an MD5 checksum into the image. Note that without an MD5 checksu, the image verification check might fail (the
rd.live.check
option in the boot loader configuration) and the installation can hang.#
implantisomd5 ../NEWISO.isoIn the above example, replace ../NEWISO.iso with the file name and the location of the ISO image that you have created in the previous step.
You can now write the new ISO image to physical media or a network server to boot it on physical hardware, or you can use it to start installing a virtual machine.
Additional resources
- For instructions on preparing boot media or network server, see Performing an advanced RHEL Installation.
- For instructions on creating virtual machines with ISO images, see Configuring and Managing Virtualization.