Clarification on NodeGetVolumeStats Behavior and Required Feature Gate for Volume Health and PVC Usage Monitoring

[adarsh-dell]

According to the documentation, enabling the feature gate is necessary to utilize this feature. In one of our OCP clusters, I observed that NodeGetVolumeStats is being called by the node service of the CSI driver container. Could someone please clarify if this behavior is expected? If so, what specific functionality requires the feature gate to be enabled at the cluster level?

We have enabled this feature to monitor volume health and to track PVC usage, including remaining and used capacity.

Thanks,
Adarsh

[xing-yang]

Sorry, I missed this issue earlier. "used" capacity is part of NodeGetVolumeStats that is already GA. It is not controlled by the volume health feature gate. Volume health feature gate enables VolumeConditionAbnormal events to be reported and corresponding metric to be emitted: https://kubernetes.io/blog/2021/04/16/volume-health-monitoring-alpha-update/#node-side-volume-health-monitoring