disk-expansion.md

Disk expansion

For some storage methods, Kubernetes may support expanding storage in-use (allowVolumeExpansion feature). KubeVirt can respond to it by making the additional storage available for the virtual machines. This feature is currently off by default, and requires enabling a feature gate. To enable it, add the ExpandDisks feature gate in the kubevirt object:

kubectl edit kubevirt -n kubevirt kubevirt

spec:
  configuration:
    developerConfiguration:
      featureGates:
      - ExpandDisks

Enabling this feature does two things:

• Notify the virtual machine about size changes
• If the disk is a Filesystem PVC, the matching file is expanded to the remaining size (while reserving some space for file system overhead).