Build haproxy images

This how-to describes the process of building a custom base image for your infrastructure, instead of having to rely on the default simplestreams server.

The haproxy image will be used for the cluster load balancer when using the development cluster template.

Table Of Contents

• Requirements
• Build image-builder binary
• Build haproxy image
• Check image
• Use the image in LXCCluster

Requirements

• A locally configured Incus or Canonical LXD instance. The image-builder utility will use the default client credentials.
• Go 1.23.0+

Build image-builder binary

First, clone the cluster-api-provider-incus source repository:

git clone https://github.com/lxc/cluster-api-provider-incus

Then, build the image-builder binary with:

make image-builder

Build haproxy image

Use ./bin/image-builder haproxy --help for a list of all available options.

./bin/image-builder haproxy --v=4 --output image-haproxy.tar.gz \
  --image-alias haproxy/u24 \
  --ubuntu-version 24.04

This will build a haproxy image based on Ubuntu 24.04, save it on the server as haproxy/u24 and also export it to the local file image-haproxy.tar.gz

Check image

incus image list haproxy

lxc image list haproxy

The output should look similar to this:

+-------------+--------------+--------+------------------------------------+--------------+-----------+-----------+-----------------------+
|    ALIAS    | FINGERPRINT  | PUBLIC |            DESCRIPTION             | ARCHITECTURE |   TYPE    |   SIZE    |      UPLOAD DATE      |
+-------------+--------------+--------+------------------------------------+--------------+-----------+-----------+-----------------------+
| haproxy/u24 | 80aef76c0754 | yes    | haproxy noble amd64 (202504280141) | x86_64       | CONTAINER | 148.15MiB | 2025/04/28 01:41 EEST |
+-------------+--------------+--------+------------------------------------+--------------+-----------+-----------+-----------------------+

Use the image in LXCCluster

Set spec.loadBalancer.instanceSpec.image.name on the LXCCluster resource of your workload cluster. When launching the cluster, this will now use our custom image to provision the load balancer.

---
apiVersion: infrastructure.cluster.x-k8s.io/v1alpha2
kind: LXCCluster
metadata:
  name: example-cluster
spec:
  secretRef:
    name: example-secret
  loadBalancer:
    lxc:
      instanceSpec:
        flavor: c1-m1
        profiles: [default]
        image:
          name: haproxy/u24