Chainguard Container for cluster-api-capd-manager

Cluster API Provider Docker (CAPD) is a reference implementation of an infrastructure provider for the Cluster API project using Docker, not designed for production use and intended for development environments only.

Chainguard Containers are regularly-updated, secure-by-default container images.

Download this Container Image

For those with access, this container image is available on cgr.dev:

docker pull cgr.dev/ORGANIZATION/cluster-api-capd-manager:latest

Be sure to replace the ORGANIZATION placeholder with the name used for your organization's private repository within the Chainguard Registry.

Compatibility Notes

Chainguard's cluster-api-capd-manager image is compatible with the upstream Cluster API Provider Docker. This image contains only the minimum set of dependencies needed to run the Docker infrastructure provider components.

The Docker provider is primarily used for testing Cluster API functionality and local development workflows.

⚠️ Important: This image is designed for testing and development purposes only and is not meant for production use.

Getting Started

The Cluster API Provider for Docker (CAPD) enables you to create and manage "clusters" using Docker containers as nodes. This is particularly useful for testing Cluster API functionality, local development, and CI/CD pipelines where you need lightweight Kubernetes clusters.

Prerequisites

• A management cluster with Cluster API core components installed
• clusterctl CLI tool
• Docker daemon running and accessible

Installation

Initialize the Docker infrastructure provider using clusterctl:

clusterctl init --infrastructure docker

Or manually install using the Chainguard image by applying the InfrastructureProvider resource:

kubectl apply -f - <<EOF
apiVersion: operator.cluster.x-k8s.io/v1alpha2
kind: InfrastructureProvider
metadata:
  name: docker
  namespace: docker-infrastructure-system
spec:
  version: v1.10.4
  deployment:
    containers:
    - name: manager
      imageUrl: cgr.dev/ORGANIZATION/cluster-api-capd-manager:latest
EOF

Usage Example

Create a Docker-based cluster using Cluster API resources:

apiVersion: infrastructure.cluster.x-k8s.io/v1beta1
kind: DockerCluster
metadata:
  name: test-docker-cluster
  namespace: default
spec: {}
---
apiVersion: infrastructure.cluster.x-k8s.io/v1beta1
kind: DockerMachineTemplate
metadata:
  name: test-control-plane
  namespace: default
spec:
  template:
    spec:
      extraMounts:
      - containerPath: /var/run/docker.sock
        hostPath: /var/run/docker.sock

Configuration

The controller manages Docker containers that simulate Kubernetes nodes. Key features include:

• Container-based nodes: Each "node" is a Docker container running systemd and kubelet
• Load balancer simulation: Automatic setup of load balancer containers for API server access
• Port mapping: Automatic port allocation for accessing services
• Volume mounts: Support for mounting host directories into node containers

Testing and Development Use Cases

• Cluster API development: Test control plane and infrastructure provider changes
• CI/CD pipelines: Automated testing of Kubernetes workloads
• Learning environment: Practice with Cluster API concepts without cloud resources
• Integration testing: Validate multi-cluster scenarios locally

Documentation and Resources

• Cluster API Getting Started Documentation
• Cluster API Documentation
• Docker Documentation

What are Chainguard Containers?

Chainguard's free tier of Starter container images are built with Wolfi, our minimal Linux undistro.

All other Chainguard Containers are built with Chainguard OS, Chainguard's minimal Linux operating system designed to produce container images that meet the requirements of a more secure software supply chain.

The main features of Chainguard Containers include:

• Minimal design, without unnecessary software bloat
• Daily builds to ensure container images are up-to-date with available security patches
• High quality build-time SBOMs attesting to the provenance of all artifacts within the image
• Verifiable signatures provided by Sigstore
• Reproducible builds with Cosign and apko (read more about reproducibility)

For cases where you need container images with shells and package managers to build or debug, most Chainguard Containers come paired with a development, or -dev, variant.

In all other cases, including Chainguard Containers tagged as :latest or with a specific version number, the container images include only an open-source application and its runtime dependencies. These minimal container images typically do not contain a shell or package manager.

Although the -dev container image variants have similar security features as their more minimal versions, they include additional software that is typically not necessary in production environments. We recommend using multi-stage builds to copy artifacts from the -dev variant into a more minimal production image.

Need additional packages?

To improve security, Chainguard Containers include only essential dependencies. Need more packages? Chainguard customers can use Custom Assembly to add packages, either through the Console, chainctl, or API.

To use Custom Assembly in the Chainguard Console: navigate to the image you'd like to customize in your Organization's list of images, and click on the Customize image button at the top of the page.

Learn More

Refer to our Chainguard Containers documentation on Chainguard Academy. Chainguard also offers VMs and Libraries — contact us for access.

Trademarks

This software listing is packaged by Chainguard. The trademarks set forth in this offering are owned by their respective companies, and use of them does not imply any affiliation, sponsorship, or endorsement by such companies.