Tanzu Mission Control – Cluster UpgradeMarch 10, 2020
Kubernetes releases a new minor version every quarter and updating your existing clusters can be a chore. With updates coming at you pretty quickly and new functionality being added all the time, having a way to upgrade your clusters is a must, especially if you are managing multiples of clusters. Tanzu Mission Control can take the pain out of upgrading these clusters.
It should be mentioned that the cluster upgrade procedure only works for clusters that were previously deployed through Tanzu Mission Control. If an existing cluster is attached to TMC after deployment, these cluster lifecycle steps won’t work.
Perform a Cluster Upgrade
Upgrading a cluster provisioned by TMC is a very straightforward process. Through the use of control loops in Tanzu Mission Control code, the cluster version is updated and the TMC intelligence does the rest.
For this example, we’ll find the cluster used in previous posts deployed on AWS with version. 1.16.4 as seen from the command line result of get nodes.
Now, lets login to the Tanzu Mission Control console and find our cluster in the clusters menu.
In the upper right hand corner of this screen you can see a highlighted “Upgrade” button. Click that button and we’re on our way. The next screen that is displayed will warn you that lifecycle operations will be suspended during this process and as all upgrades, you should always have a good backup before continuing. You’ll then select the version that you’d like to upgrade the cluster to.
Note: You will only be able to select versions newer than the existing version. There is no version rollback functionality built into this tool if you decide you needed to downgrade the cluster version.
When you’re ready, click upgrade and then sit back and relax while TMC does the work.
While the cluster is upgrading, you’ll see the upgrading status at the top of the page.
If you are closely watching the nodes, you can see that they will be in differing verisions while the cluster is in the upgrade process. For example, you can see I have nodes in two different versions seen below.
When you’re all done, you’ll have a healthy upgraded cluster. Now you can repeat this on the rest of the clusters under TMC management if you need to.