Upgrading a Kubernetes cluster using kubeadm
Kubernetes versions follow semantic versioning, and are expressed in three parts:
- Major version
- Minor version
- Patch version
For example, Kubernetes version 1.23.3 means that it is Kubernetes 1.23 minor version with patch number 3. Similarly, 1.22 and 1.21 are both minor versions like 1.23.
At the time of writing this book, Kubernetes 1.19+ has one year of path support. That means for Kubernetes 1.23, released in January 2022, the end of support will be February 2023. For Kubernetes 1.8 and older, the support patch was shortened to roughly 9 months instead. Special interest group (SIG) releases manage the Kubernetes release cycle, and the best way to keep track of the release schedule is to follow them at https://github.com/kubernetes/sig-release/tree/master/releases and read the change log at https://github.com/kubernetes/kubernetes/tree/master/CHANGELOG to keep up to date.
If you would like to upgrade a cluster...
