This is adapted from: https://cluster-api.sigs.k8s.io/tasks/upgrading-clusters.html

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It’s recommended to regularly upgrade your clusters. This avoids trying to maintain tooling version compatibility against major Kubernetes versions.

OS Patches

The operating system and associated packages can be updated independently, e.g. to apply security patches to the host OS.

The Ubuntu image is stripped so the packages (and number of vulnerabilities) is significantly lower. The Cloud team will make it clear when a CVE applies to the CAPI Ubuntu images.

Skip to https://stfc.atlassian.net/wiki/spaces/CLOUDKB/pages/285704256/Cluster+API+Upgrade#Kubernetes-Image-and-Version-Upgrades .

Multiple Version Upgrades

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To upgrade major versions you will need to follow the https://stfc.atlassian.net/wiki/spaces/CLOUDKB/pages/285704256/Cluster+API+Upgrade#Upgrade-Clusterctl-and-CAPI-components section first then https://stfc.atlassian.net/wiki/spaces/CLOUDKB/pages/285704256/Cluster+API+Upgrade#UpgradingUpgrade#Kubernetes-KubernetesImage-Majorand-Version-Upgrades for each hop.

Overview

This process assumes the administrator is doing a full upgrade of all components. These can be upgraded independently with the caveat that the Infrastructure layer supports the version of Kubernetes planned: https://cluster-api.sigs.k8s.io/reference/versions

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Update the helm Cluster API charts:

# Update URLs to repos if required:
helm repo add capi https://azimuth-cloud.github.io/capi-helm-charts --force-update
helm repo add capi-addons https://azimuth-cloud.github.io/cluster-api-addon-provider --force-update

# Avoid updating openstack-cluster chart until later
helm repo update capi-addons

helm upgrade cluster-api-addon-provider capi-addons/cluster-api-addon-provider -n clusters --wait
cd <folder_with_values>

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• Validate that the upgrade is valid and apply the command provided by clusterctl

Kubernetes Image and Version Upgrades

Without minor version upgrade

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You’ll need to upgrade VM images and Kubernetes version to the latest patch version available

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before doing any major upgrades:

I.e. if you’re on 1.100.12 upgrade to the latest 1.100.x, this ensures any bug-fixes are applied which could prevent later upgrades.

For major and minor

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upgrades

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:

• Lookup the latest image build for Kubernetes, this can be found in images section of the web interface

• Edit the kubernetesVersion in user-values.yaml

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• to

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• match the image name

• Edit the machineImage in user-values.yaml

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• to

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• use the latest patch release

helm repo update capi
helm upgrade <cluster_name> capi/openstack-cluster -f values.yaml -f clouds.yaml -f user-values.yaml -f flavors.yaml -n clusters

• Wait for the rollout of new infra to complete

  • The rollout can be monitored with kubectl get kcp -A and kubectl get md -A

  • Machine details can be found in kubectl get machines -A and kubectl get openstackmachines -A

With minor version upgrade

• Upgrade to the

• Repeat for each major upgrade step

  • You can only do a single major upgrade at a time, e.g. 1.100.12 to 1.101.4, then 1.102.6

Supported Kubernetes Versions

We aim to support Kubernetes versions and keep CAPI images for N -1 → all supported End of Life (EOL) versions from: https://kubernetes.io/releases/ OR the oldest CAPI image we have that gives an upgrade path - whichever is the older; where N is the latest Kubernetes version.

For example, as of the 29/01/2025, the latest Kubernetes version is v1.32 and therefore, we will provide CAPI images for Kubernetes versions v1.31 → v1.26 (oldest image we hold).

• Once we provide the latest N-1 image, we will keep the oldest image (v1.26) for a minimum of 4 weeks to let you upgrade older clusters and notify any users accordingly.

Image Added

Troubleshooting

On the management cluster

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