:_mod-docs-content-type: ASSEMBLY
[id="installing-customizing"]
= Customizing nodes
include::_attributes/common-attributes.adoc[]
:context: installing-customizing

toc::[]

[role="_abstract"]
You can customize nodes both cluster-wide and per-machine configuration through Ignition, which allows arbitrary partitioning and file content changes to the operating system. 

If a configuration file is documented in {op-system-base-full}, you can modify the file through Ignition.

There are two ways to deploy machine config changes:

* Creating machine configs that are included in manifest files to start up a cluster during `openshift-install`.

* Creating machine configs that are passed to running {product-title} nodes through the Machine Config Operator.

Additionally, modifying the reference config, such as the Ignition config that is passed to `coreos-installer` when installing bare-metal nodes allows per-machine configuration. The Machine Config Operator cannot yet see these changes.

The following sections describe features that you might want to configure on your nodes.

include::modules/installation-special-config-butane.adoc[leveloffset=+1]

include::modules/installation-special-config-butane-about.adoc[leveloffset=+2]

[role="_additional-resources"]
.Additional resources

* link:https://coreos.github.io/butane/specs/[Butane config specification]

include::modules/installation-special-config-butane-install.adoc[leveloffset=+2]

include::modules/installation-special-config-butane-create.adoc[leveloffset=+2]

[role="_additional-resources"]
[id="additional-resources_{context}"]
== Additional resources

* xref:../../installing/install_config/installing-customizing.adoc#installation-special-config-kmod_installing-customizing[The addition of kernel modules to nodes]
* xref:../../installing/install_config/installing-customizing.adoc#installation-special-config-storage_installing-customizing[Encrypting and mirroring disks during installation]

include::modules/installation-special-config-kargs.adoc[leveloffset=+1]

[role="_additional-resources"]
.Additional resources

* link:https://www.kernel.org/doc/Documentation/admin-guide/kernel-parameters.txt[Kernel.org kernel parameters]

include::modules/installation-special-config-kmod.adoc[leveloffset=+1]

include::modules/building-testing-kernel-module-container.adoc[leveloffset=+1]

include::modules/provisioning-kernel-module-to-ocp.adoc[leveloffset=+1]

include::modules/provision-kernel-modules-via-machineconfig.adoc[leveloffset=+2]

[role="_additional-resources"]
.Additional resources

* link:https://github.com/kmods-via-containers/kmods-via-containers[kmods-via-containers (GitHub)]

include::modules/installation-special-config-storage.adoc[leveloffset=+1]

include::modules/installation-special-config-encryption-threshold.adoc[leveloffset=+2]

include::modules/installation-special-config-mirrored-disk.adoc[leveloffset=+1]

include::modules/installation-special-config-storage-procedure.adoc[leveloffset=+2]

[role="_additional-resources"]
== Additional resources

* link:https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/{op-system-version-9}/html/security_hardening/configuring-automated-unlocking-of-encrypted-volumes-using-policy-based-decryption_security-hardening#network-bound-disk-encryption_configuring-automated-unlocking-of-encrypted-volumes-using-policy-based-decryption[Network-bound disk encryption]

* link:https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/{op-system-version-9}/html-single/security_hardening/index#proc_installing-the-system-with-fips-mode-enabled_switching-rhel-to-fips-mode[Installing the system in FIPS mode]

* link:https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/{op-system-version-9}/html/security_hardening/configuring-automated-unlocking-of-encrypted-volumes-using-policy-based-decryption_security-hardening[Configuring automated unlocking of encrypted volumes using policy-based decryption]

include::modules/installation-special-config-raid.adoc[leveloffset=+1]

include::modules/installation-special-config-raid-intel-vroc.adoc[leveloffset=+1]

include::modules/installation-special-config-chrony.adoc[leveloffset=+1]

[role="_additional-resources"]
.Additional resources

* xref:../../installing/install_config/installing-customizing.adoc#installation-special-config-butane_installing-customizing[Creating machine configs with Butane]

ifndef::openshift-origin[]
* xref:../../installing/overview/installing-fips.adoc#installing-fips[Support for FIPS cryptography]
endif::[]
