CSI Driver and Volume Snapshots

CSI Driver and Volume Snapshots

Overview

This tutorial explains how to set up the CSI Hostpath Driver in minikube and create volume snapshots.

Prerequisites

  • latest version of minikube

Tutorial

Support for volume snapshots in minikube is provided through the volumesnapshots addon. This addon provisions the required CRDs and deploys the Volume Snapshot Controller. It is disabled by default.

Furthermore, the default storage provider in minikube does not implement the CSI interface and thus is NOT capable of creating/handling volume snapshots. For that, you must first deploy a CSI driver. To make this step easy, minikube offers the csi-hostpath-driver addon, which deploys the CSI Hostpath Driver. This addon is disabled by default as well.

Thus, to utilize the volume snapshots functionality, you must:

1) enable the volumesnapshots addon AND
2a) either enable the csi-hostpth-driver addon OR
2b) deploy your own CSI driver

You can enable/disable either of the above-mentioned addons using

minikube addons enable [ADDON_NAME]
minikube addons disable [ADDON_NAME]

The csi-hostpath-driver addon deploys its required resources into the kube-system namespace and sets up a dedicated storage class called csi-hostpath-sc that you need to reference in your PVCs. The driver itself is created under the name hostpath.csi.k8s.io. Use this wherever necessary (e.g. snapshot class definitions).

Once both addons are enabled, you can create persistent volumes and snapshots using standard ways (for a quick test of volume snapshots, you can find some example yaml files along with a step-by-step here). The driver stores all persistent volumes in the /var/lib/csi-hostpath-data/ directory of minikube’s host.