Kubernetes and companies that provide support for Kubernetes traditionally honor the three most recent minor releases. So if 1.18 is the current stable release, software will be officially supported for 1.16 and 1.17 as well. When 1.19 comes out, 1.16 will fall off the bottom of the stack.
This means that you will need to upgrade Kubernetes often over the life of your cluster.
You do this by first upgrading RKE on your host system. Each version of RKE has a specific list of supported Kubernetes versions, which you can find by running
rke config --list-versions --all.
Make a one-time snapshot of etcd on the cluster. This is always a good practice.
When the snapshot is complete, and you know what version you’re upgrading to, edit cluster.yml and set that version in the kubernetes_version key.
rke up, and a short while later your cluster will be upgraded to the new version.
rke configto list the versions of Kubernetes supported by this version of rke.
- In Lab 2 you should have a selected one that is not the most recent. Now, you’ll upgrade the cluster to the latest version.
- Modify your cluster configuration file, using the new Kubernetes version
rke upto deploy the cluster to the single node.
- RKE will have created several files. Keep these in a safe place.
- You can now use the
kubectlto test access to the cluster.
- Upgrading RKE - https://rancher.com/docs/rke/latest/en/upgrades/
- How Upgrades Work - https://rancher.com/docs/rke/latest/en/upgrades/how-upgrades-work/
- Upgrades - https://rancher.com/docs/rke/latest/en/upgrades/
- Save Your Files - https://rancher.com/docs/rke/latest/en/installation/#save-your-files
- Listing Supported Kubernetes Versions - https://rancher.com/docs/rke/latest/en/upgrades/#listing-supported-kubernetes-versions