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Image Builder Guide
3.7. Supported Image Customizations

3.7. Supported Image Customizations

A number of image customizations are supported in blueprints. In order to make use of these options, you need to initially configure them in the blueprint and then use the command push to import the modified blueprint to Image Builder.

Note

These customizations are not currently supported in the accompanying `cockpit-composer` GUI.

Set the image host name

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[customizations]
hostname = "baseimage"

[customizations]
hostname = "baseimage"

User specifications for the resulting system image

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[[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

[[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

Only the user name is required, you can leave out any other lines.

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

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

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

Important

To generate the hash, you must have the python3 package on your system. Use the following command to install the package:

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yum install python3

# yum install python3

Replace PUBLIC-SSH-KEY with the actual public key.

Repeat this block for every user you want to include.

Group specifications for the resulting system image

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

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

Repeat this block for every group you want to include.

Set an existing user's ssh key

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[[customizations.sshkey]]
user = "root"
key = "PUBLIC-SSH-KEY"

[[customizations.sshkey]]
user = "root"
key = "PUBLIC-SSH-KEY"

Note

This option is only applicable for existing users. To create a user and set an ssh key, use the User specifications for the resulting system image customization.

Append a kernel boot parameter option to the defaults

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[[customizations.kernel]]
append = "KERNEL-OPTION"

[[customizations.kernel]]
append = "KERNEL-OPTION"

Set the image host name

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[customizations]
hostname = "BASE-IMAGE"

[customizations]
hostname = "BASE-IMAGE"

Add a group for the resulting system image

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

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

Only the name is required and GID is optional.

Set the timezone and the Network Time Protocol (NTP) servers for the resulting system image

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[customizations.timezone]
timezone = "TIMEZONE"
ntpservers = NTP-SERVER

[customizations.timezone]
timezone = "TIMEZONE"
ntpservers = NTP-SERVER

If you do not set a timezone, the system uses Universal Time, Coordinated (UTC) as default. Setting NTP servers is optional.

Set the locale settings for the resulting system image

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[customizations.locale]
language = "[LANGUAGE]"
keyboard = "KEYBOARD"

[customizations.locale]
language = "[LANGUAGE]"
keyboard = "KEYBOARD"

Setting both language and keyboard options is mandatory. You can add multiple languages. The first language you add will be the primary language and the other languages will be secondary.

Set the firewall for the resulting system image

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

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

You can use the numeric ports, or theirs names from the `/etc/services` file to enable or disable lists.

Set which services to enable during the boot time

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

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

You can control which services to enable during the boot time. Some image types already have services enabled or disabled so that the image works correctly and this setup cannot be overridden.

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