[FEATURE] Kubernetes snapshot support (csi-snapshotter)

[yasker]

In Kubernetes 1.12, the snapshot support will be added. We will evaluate the feature and if it goes well, we will add the support for it.

The doc is at:
https://github.com/kubernetes/community/blob/master/contributors/design-proposals/storage/csi-snapshot.md

The external snapshotter:
https://github.com/kubernetes-csi/external-snapshotter

[lomori]

Any estimates for when the CSI Volume Snapshot is going to be available?

[joshimoo]

@lomori csi snapshot support is going to be included in the longhorn 1.1 release which is targeting early November.
After this issue is closed, it will be available in the master branch and can be used for testing.

[joshimoo]

Document outlining the kubernetes snapshot support changes between the alpha and beta csi snapshot support.
https://github.com/kubernetes/enhancements/tree/master/keps/sig-storage/177-volume-snapshot#controller-split

[khushboo-rancher]

Verified on longhorn Master - 09/14/2020

Validation - Pass

Executed the test cases from https://rancher.atlassian.net/wiki/spaces/LON/pages/735379688/CSI+Snapshot+Support

Once #1788 is closed, we are good to close this feature.

[joshimoo]

@khushboo-rancher is this issue good to close?

[khushboo-rancher]

Functionality has been validated manually and right now the implementation of integration tests for this feature is in progress.
We can close this issue and create one for the integration test implementation if we want.

[joshimoo]

@khushboo-rancher thanks no problem you can keep it open then, was just following up :)

[yasker]

It's unlikely we have time for writing the automation test for this issue in v1.1.0. Let's do a regression test and then punt it to v1.1.1 release.

[PhanLe1010]

Revalidated manually: Pass