Support volume resize

[tobru]

What did you do? (required. The issue will be closed when not provided.)

Tried to change size of a PVC.

What did you expect to happen?

Volume get's resized.

• CSI Version: dev
• Kubernetes Version: 1.11
• Cloud provider/framework version, if applicable (such as Rancher): Rancher

Error logged when PVC gets edited:

error: persistentvolumeclaims "csi-pvc1" could not be patched: persistentvolumeclaims "csi-pvc1" is forbidden: only dynamically provisioned pvc can be resized and the storageclass that provisions the pvc must support resize

[davidhalter]

Resizing PVC's is currently not part of the CSI spec (see https://github.com/container-storage-interface/spec/blob/v0.3.0/spec.md). There are a number of tickets in the CSI spec issue tracker that try to make resizing part of the spec. Note that Kubernetes support for this would also needed to be done for that. I suppose we are speaking of 3+ months at least.

container-storage-interface/spec#212
container-storage-interface/spec#222

I will close this ticket and wait until it's supported in Kubernetes & the CSI spec.

[srueg]

The volume expansion made it to the spec, any plans to implement it? https://kubernetes-csi.github.io/docs/volume-expansion.html

[davidhalter]

We currently don't have plans for this, but we will discuss it internally.

[alakae]

Feature is available in latest release.