Upgrading from 1.2 to 1.3

This document contains important upgrade notes for upgrading from KubeOne 1.2 to 1.3. For the complete changelog, please check the complete v1.3.0 changelog on GitHub.

Support and Compatibility Policy Changes

The KubeOne 1.3 release brings some changes to the support and compatibility policies.

Kubernetes

The minimum supported Kubernetes version is now 1.19.0. If you have Kubernetes clusters running 1.18 or older, you need to use an older KubeOne release to upgrade those clusters to v1.19 before upgrading to KubeOne 1.3. Check out the Compatibility guide for more information about supported Kubernetes versions for each KubeOne release.

The Kubernetes 1.22 release is officially supported starting with this release.

We recommend using a Kubernetes release that’s not older than one minor release than the latest Kubernetes release. For example, with 1.22 being the latest release, we recommend running at least Kubernetes 1.21.

Terraform

In addition, the minimum Terraform version is now 1.0.0. All example Terraform configurations provided by KubeOne work only with Terraform 1.0.0 or newer. You might be able to continue using an older version of Terraform with existing/older configurations, but we don’t provide any support for older Terraform versions and we strongly recommend upgrading to 1.0.0 as soon as possible.

You can check the following KubeOne PR as an example how to modify existing Terraform configurations to support Terraform 1.0 and newer.

Operating Systems

Starting with this release, we’re dropping support for Debian 10, Debian 11, and RHEL 7 clusters. If you have a Debian cluster, we recommend switching to other operating system such as Ubuntu. If you have a RHEL 7 cluster, we recommend switching to RHEL 8 which is supported.

Support for CentOS 8 clusters is deprecated starting with KubeOne 1.3 release and it will be entirely removed in KubeOne 1.4. CentOS 8 announced that it will reach End-Of-Life (EOL) on December 31, 2021. CentOS 7 remains supported by KubeOne for now.

We’re researching about supporting alternative CentOS distributions and we’ll provide updates accordingly. In meanwhile, if you have any feedback on which distribution should we support instead, feel free to create a GitHub issue or reach out to us over product@kubermatic.com.

Amazon Linux 2 is now a supported operating system for general Kubernetes clusters.

kubeone reset Confirmation

The kubeone reset command requires an explicit confirmation like the apply command. This change has been announced with KubeOne 1.2 release, and it’s now in the effect. Running the command will show a recap of which nodes will be reset and which Machines will be destroyed. The command can be approved by typing yes or using the --auto-approve flag.

If you’re using kubeone reset as part of an automated script (e.g. in a CI pipeline), you should adjust your scripts to use the --auto-approve flag, so you’re not asked to explicitly confirm the command.

Addons Reorganization

KubeOne Addons can now be organized into subdirectories. It currently remains possible to put addons in the root of the addons directory, however, this is option is considered as deprecated as of this release. We highly recommend all users to reorganize their addons into subdirectories, where each subdirectory is for YAML manifests related to one addon.

Example Reorganization

For example, if you provided ./addons as the addons directory (using .addons.path in the KubeOneCluster manifest), you should move all YAML manifest located in the root of ./addons directory to dedicated subdirectories.

Let’s say you have two YAML manifests — one for cluster-autoscaler and another for backups. Your ./addons directory currently looks like this:

addons
├── backups-restic.yaml
└── cluster-autoscaler.yaml

After the reorganization, the ./addons directory should look like this:

addons
├── backups-restic
│   └── backups-restic.yaml
└── cluster-autoscaler
    └── cluster-autoscaler.yaml

Addons can be organized into subdirectories, but only one level of subdirectories is supported. For example, ./addons/example-addon-1 is supported and YAML manifest in that directory will be deployed, but ./addons/example-addon-1/subdirectory-2 directory will be entirely ignored.

Automatically Deploying the CSI Plugins

The CSI plugin is now deployed automatically for Hetzner, OpenStack, and vSphere clusters with external cloud provider (i.e. .cloudProvider.external enabled).

vSphere CSI plugin requires the CSI configuration to be provided via the newly-added cloudProvider.csiConfig field. If it’s not provided, the CSI plugin will not be automatically deployed. More information about the CSI plugin configuration can be found in the vSphere CSI docs. In addition, the vSphere CSI plugin requires vSphere version 6.7u3.

The default StorageClass is not deployed by default. It can be deployed via new Addons API by enabling the default-storage-class addon, or manually.

If you already have the CSI plugin deployed, you need to make sure that your CSI plugin deployment is compatible with the KubeOne CSI plugin addon. You can find the CSI addons in the addons directory in the GitHub repository.

If your CSI plugin deployment is incompatible with the KubeOne CSI addon, you can resolve it in one of the following ways:

  • Delete your CSI deployment and let KubeOne install the CSI driver for you. Note: you’ll not be able to mount volumes until you don’t install the CSI driver again.
  • Override the appropriate CSI addon with your deployment manifests. With this way, KubeOne will install the CSI plugin using your manifests. To do this, check out the Overriding Embedded Addons section of the Addons document for instructions.

Known Issues

  • It’s currently not possible to provision or upgrade to Kubernetes 1.22 for clusters running on vSphere. This is because vSphere CCM and CSI don’t support Kubernetes 1.22. We’ll introduce Kubernetes 1.22 support for vSphere as soon as new CCM and CSI releases with support for Kubernetes 1.22 are out.
  • Newly-provisioned Kubernetes 1.22 clusters or clusters upgraded from Kubernetes 1.21 to 1.22 using KubeOne 1.3.0-alpha.1 use a metrics-server version incompatible with Kubernetes 1.22. This might impact deleting Namespaces that manifests by the Namespace being stuck in the Terminating state. This can be fixed by upgrading KubeOne to v1.3.0-rc.0 or newer and running kubeone apply.
  • The new Addons API requires the addons directory path (.addons.path) to be provided and the directory must exist (it can be empty), even if only embedded addons are used. If the path is not provided, it’ll default to ./addons.