k0s supports a wide range of different storage options by utilizing Container Storage Interface (CSI). All Kubernetes storage solutions are supported and users can easily select the storage that fits best for their needs.
When the storage solution implements CSI, kubernetes can communicate with the storage to create and configure persistent volumes. This makes it easy to dynamically provision the requested volumes. It also expands the supported storage solutions from the previous generation, in-tree volume plugins. More information about the CSI concept is described on the Kubernetes Blog.
Installing 3rd party storage solutions#
Follow your storage driver's installation instructions. Note that by default the Kubelet installed by k0s uses a slightly different path for its working directory (
/varlib/k0s/kubelet instead of
/var/lib/kubelet). Consult the CSI driver's configuration documentation on how to customize this path. The actual path can differ if you defined the flag
Example storage solutions#
Different Kubernetes storage solutions are explained in the official Kubernetes storage documentation. All of them can be used with k0s. Here are some popular ones:
- Rook-Ceph (Open Source)
- MinIO (Open Source)
- Gluster (Open Source)
- Longhorn (Open Source)
- Amazon EBS
- Google Persistent Disk
- Azure Disk
If you are looking for a fault-tolerant storage with data replication, you can find a k0s tutorial for configuring Ceph storage with Rook in here.
Bundled OpenEBS storage (deprecated)#
Bundled OpenEBS was deprecated in favor of running it as a helm extension, this documentation is maintained as a reference for existing installations.
This was done for three reasons:
- By installing it as a helm extension, users have more control and flexibility without adding complexity.
- It allows users to choose the OpenEBS version independent of their k0s version.
- It makes the k0s configuration more consistent.
For new installations or to migrate existing installations, please refer to the OpenEBS extension page.
The OpenEBS extension is enabled by setting
The cluster will have two storage classes available for you to use:
k0s kubectl get storageclass
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
openebs-device openebs.io/local Delete WaitForFirstConsumer false 24s
openebs-hostpath openebs.io/local Delete WaitForFirstConsumer false 24s
openebs-hostpath is the storage class that maps to the
Use following manifests as an example of pod with mounted volume:
- image: nginx
- name: persistent-storage
- name: persistent-storage
k0s kubectl apply -f nginx.yaml
bash-5.1# k0s kc get pods
NAME READY STATUS RESTARTS AGE
nginx-d95bcb7db-gzsdt 1/1 Running 0 30s
k0s kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-9a7fae2d-eb03-42c3-aaa9-1a807d5df12f 5Gi RWO Delete Bound default/nginx-pvc openebs-hostpath 30s