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Storage Class

Take me to Lecture

In this section, we will take a look at Storage Class

We discussed about how to create Persistent Volume and Persistent Volume Claim and We also saw that how to use into the Pod’s volume to claim that volume space.
We created Persistent Volume but before this if we are taking a volume from Cloud providers like GCP, AWS, Azure. We need to first create disk in the Google Cloud as an example.
We need to create manually each time when we define in the Pod definition file. that’s called Static Provisioning.

Static Provisioning

class-18

Dynamic Provisioning

class-19

Now we have a Storage Class, So we no longer to define Persistent Volume. It will create automatically when a Storage Class is created. It’s called Dynamic Provisioning.

sc-definition.yaml

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   name: google-storage
provisioner: kubernetes.io/gce-pd

Create a Storage Class

$ kubectl create -f sc-definition.yaml
storageclass.storage.k8s.io/google-storage created

List the Storage Class

$ kubectl get sc
NAME             PROVISIONER            RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
google-storage   kubernetes.io/gce-pd   Delete          Immediate           false                  20s

Create a Persistent Volume Claim

pvc-definition.yaml

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: myclaim
spec:
  accessModes: [ "ReadWriteOnce" ]
  storageClassName: google-storage       
  resources:
   requests:
     storage: 500Mi

$ kubectl create -f pvc-definition.yaml

Create a Pod

pod-definition.yaml

apiVersion: v1
kind: Pod
metadata:
  name: mypod
spec:
  containers:
    - name: frontend
      image: nginx
      volumeMounts:
      - mountPath: "/var/www/html"
        name: web
  volumes:
    - name: web
      persistentVolumeClaim:
        claimName: myclaim

$ kubectl create -f pod-definition.yaml

Provisioner

class-20

Kubernetes Storage Class Reference Docs

https://kubernetes.io/docs/concepts/storage/storage-classes/
https://cloud.google.com/kubernetes-engine/docs/concepts/persistent-volumes#storageclasses
https://docs.aws.amazon.com/eks/latest/userguide/storage-classes.html