vSphere 8 U2 CNS Feature Highlight
With the announcement of vSphere 8 Update 2, I wanted to highlight a few CNS/CSI features in this update.
With each update release of vSphere, the Tanzu/CNS team continues to improve and enhance K8s capabilities. Whether that’s directly in Tanzu or using the CSI interface in the vSphere environment. With this release, there are a few new features in CNS that will help DevOps admins manage PV/PVCs placement and storage maintenance easier.
1) CSI Snapshots for TKG service.
In previous releases, users were unable to take PV (Persistent Volume) snapshots directly using CSI (Container Storage Integration). In vSphere 8.0 Update 2, we’ve added the capability for users and backup vendors to take PV snapshots in TKGS. This will help admins with backups or updates to K*s applications.
2) Use svMotion to migrate PV/PVCs from one datastore to another.
This feature helps DevOps or VI admins relocate volumes without having to rebuild a K8s application. This also integrates with SPBM (Storage Policy Based Management) in vCenter. You can now relocate volume(s) of deployed applications to a new or temporary locations. NOTE: while the volume is being relocated, the volume will be locked causing the application to be paused during migration.
How is this useful?
Let’s say you need to change or EOL a datastore and you have deployed K8s applications to the datastore. Previously, you would have to either rebuild to the new datastore or power off the application and manually relocate the volumes. Either way, this was not a simple task and resulted in an impact on the applications.
As they say, a picture is worth a thousand words, so a video must be worth much more.
Here’s a short video showing the live migration of a PVC from one datastore to another. In the video, I do not change or update the SPBM policy on purpose. I wanted to show a use case of moving a PVC temporarily for something like datastore maintenance. Initially, when moving the volume, it becomes non-compliant with the SPBM policy. Then I moved the volume back and the volume became compliant again. The application is a simple WordPress MySQL deployment on TKG.
For more information on these features, see the vSphere 8 U2 CNS announcement blog here.