Kubernetes versions and upgrades

Cloudfleet takes care of cluster upgrades on your behalf. We frequently upgrade the clusters as we add new Cloudfleet features without the underlying Kubernetes version not changing. We call these versions CFKE patch versions. In case of upgrading your cluster to a new CFKE patch version, most of the time the underlying Kubernetes version stays same.

Less frequently, along with the CFKE Patch Version, we also upgrade the Kubernetes version.

A minor version of Cloudfleet Kubernetes Engine (CFKE) supports all Kubernetes versions that were officially supported upstream at the time of its release. For more information on the upstream support policy, refer to the Version Skew Policy. Over time, new CFKE patch versions will add support for updated Kubernetes patch versions and phase out older ones, particularly if they are impacted by critical bugs.

CFKE will generally remove support for Kubernetes minor versions once they reach end-of-life (EOL). However, an exception may be made if upgrading to a newer Kubernetes version requires significant migration efforts, such as handling deprecated API versions. In such cases, CFKE may offer limited support for an EOL version for an additional release cycle to give you time to complete the necessary migrations.

Q: Can I access my cluster while the control plane is upgrading?

Yes. The control plane is upgraded using a rolling update strategy to ensure it remains available throughout the upgrade process.

Q: How can I ensure that cluster upgrades do not disrupt my workloads?

Currently, we do not automatically upgrade your compute nodes. We first upgrade the control plane while leaving your compute nodes untouched. If a node is deleted and recreated, the new node will be provisioned with the updated control plane version. This approach ensures your workloads are not impacted during or after the cluster upgrade and remain available.

If you wish to proactively upgrade your nodes rather than waiting for the node auto-provisioner to replace them (due to various reasons), you can drain nodes individually. This action triggers the creation of new nodes with the updated version and the subsequent deletion of the old ones.

Q: How do I upgrade self-managed nodes?

To upgrade a self-managed node, you should re-add it to the cluster. This process synchronizes the node with the current control plane version. We are planning to automate this process in the near future.