Image Builder

Please see our Book for more in-depth documentation.

What is Image Builder?

Image Builder is a tool for building Kubernetes virtual machine images across multiple infrastructure providers. The resulting VM images are specifically intended to be used with Cluster API but should be suitable for other setups that rely on Kubeadm.

Useful links

• Quick Start for Cluster API Image Builder

Provider / OS Matrix

The table below shows the currently provided operating systems for each provider built-in to image builder. (Note: This doesn't mean this is an exhaustive list of OSs each provider can support, only which are currently available within image-builder by default)

Legend:

• 💙: Image is available and is covered by CI tests
• ✅: Image is available for the provider
• ❌: Image is not available for the provider

OS	ami	azure	digitalocean	gce	hcloud	huaweicloud	maas	nutanix	oci	openstack	outscale	ova	oxide	powervs	proxmox	qemu	raw	scaleway	vultr
AlmaLinux 9	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	❌	❌	❌	❌
Amazon Linux 2	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌
Amazon Linux 2023	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌
Azure Linux 3	❌	💙	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌
CentOS 9	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌	❌
CentOS 10	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌	❌
Flatcar	✅	💙	❌	❌	✅	❌	❌	✅	❌	✅	✅	💙	❌	❌	✅	✅	✅	❌	❌
Oracle Linux 9	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌
Photon 4	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	❌	❌	❌	❌
Photon 5	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	💙	❌	❌	❌	❌	❌	❌	❌
RHEL 9	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	✅	❌	❌	❌	✅	✅	❌	❌
Rocky Linux 9	❌	❌	❌	❌	✅	❌	❌	✅	❌	✅	❌	💙	❌	❌	✅	✅	❌	✅	❌
Ubuntu 22.04	✅	💙	✅	💙	✅	✅	✅	✅	✅	✅	✅	💙	❌	❌	✅	✅	✅	✅	✅
Ubuntu 24.04	✅	💙	✅	💙	✅	❌	✅	✅	❌	✅	✅	💙	✅	❌	✅	✅	✅	✅	✅
Ubuntu 26.04	✅	💙	✅	💙	✅	❌	✅	✅	❌	✅	✅	💙	❌	❌	✅	✅	✅	✅	✅
Windows 2019	✅	💙	❌	❌	❌	❌	❌	❌	✅	❌	❌	✅	❌	❌	❌	❌	❌	❌	❌
Windows 2022	❌	💙	❌	❌	❌	❌	❌	✅	✅	❌	❌	✅	❌	❌	❌	❌	❌	❌	❌
Windows 2025	❌	💙	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌
Windows Annual	❌	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌

Community, discussion, contribution, and support

Learn how to engage with the Kubernetes community on the community page.

You can reach the maintainers of this project at:

• Image Builder office hours: Mondays (biweekly) at 08:30 PT (Pacific Time) (biweekly). Convert to your timezone.
  • Meeting Agenda / Notes (access is restricted to members of the sig-cluster-lifecycle mailing list).
  • Meeting recordings.
• Slack channel
• Mailing list

Code of conduct

Participation in the Kubernetes community is governed by the Kubernetes Code of Conduct.

Goals

• To build images for Kubernetes-conformant clusters in a consistent way across infrastructures, providers, and business needs.
  • To install all software, containers, and configuration needed by downstream tools such as Cluster API providers, to enable them to pass conformance tests
  • Support end users requirements to customize images for their business needs.
• To provide assurances in the binaries and configuration in images for purposes of security auditing and operational stability.
  • Allow introspection of artifacts, software versions, and configurations in a given image.
  • Support repeatable build processes where the same inputs of requested install versions result in the same installed binaries.
• To ensure that the creation of images is performed via well defined phases. Where users could choose specific phases that they needed.

Non-Goals

• To provide upgrade or downgrade semantics.
• To provide guarantees that the software installed provides a fully functional system.
• To prescribe the hardware architecture of the build system.