Exam CKA topic 1 question 16 discussion

Create a pvc.yaml apiVersion: v1 kind: PersistentVolumeClaim metadata: name: pv-volume spec: accessModes: - ReadWriteOnce resources: requests: storage: 10Mi storageClassName: csi-hostpath-sc kubectl create -f pvc.yaml Configure the new Pod to have ReadWriteOnce access on the volume. apiVersion: v1 kind: Pod metadata: name: web-server spec: containers: - name: web-server image: nginx volumeMounts: - mountPath: "/usr/share/nginx/html " name: pv-volume volumes: - name: pv-volume persistentVolumeClaim: claimName: pv-volume k patch pvc pv-volume -p '{"spec":{"resources":{"requests":{"storage":"70Mi"}}}}' --record

killer_sh_lab part3: Note, doesn’t work: waiting for external controller to expand this PVC

killer_sh_lab part2: vi web-server.yml apiVersion: v1 kind: Pod metadata: name: web-server spec: volumes: - name: task-pv-storage persistentVolumeClaim: claimName: pv-volume containers: - name: web-server image: nginx volumeMounts: - mountPath: "/usr/share/nginx/html" name: task-pv-storage k apply -f web-server.yml k get pvc pv-volume -o json | jq -c 'paths|join(".")' k patch -h k patch pvc pv-volume -p '{"spec":{"resources":{"requests":{"storage":"20Mi"}}}}' --record # or # update yml k apply -f pv-volume.yml --record

killer_sh_lab part 1: Note: Storage Class was changed to local-path (default) for testing purposes. # add allowVolumeExpansion: true # example apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: local-path provisioner: rancher.io/local-path allowVolumeExpansion: true vi pv-volume.yml apiVersion: v1 kind: PersistentVolumeClaim metadata: name: pv-volume spec: storageClassName: local-path accessModes: - ReadWriteOnce resources: requests: storage: 10Mi k apply -f pv-volume.yml

kubectl edit pvc pv-volume --record

@dim11 - You are correct. In my local, I am getting the same error when creating the web-server pod. I do not have storageclass, do I have to create one? If yes, what should be the provider? Any help is appreciated

When i try it in home environment i am getting follwing when i create pvc " storageclass.storage.k8s.io "csi-hostpath-sc" not found". And thats why pvc is in pending state. In exam is the storageclass already existing or do we have to troubleshoot it ourselves?

Please note that the last part of the question is to expand the PersistentVolumeClaim and record that change. The "--record" will be required otherwise we will not be able to fulfill the record requirement. # k patch pv-volume -p '{"spec":{"resources":{"requests":{"storage":"70Mi"}}}}' --record

You PVC should be apiVersion: v1 kind: PersistentVolumeClaim metadata: name: pv-volume spec: storageClassName: csi-hostpath-sc accessModes: - ReadWriteOnce resources: requests: storage: 10Mi and your pod can be like this: apiVersion: v1 kind: Pod metadata: name: web-server spec: containers: - name: nginx-container image: nginx volumeMounts: - name: pv-volume mountPath: /usr/share/nginx/html volumes: - name: pv-volume persistentVolumeClaim: claimName: pv-volume Check the stirage class already existing to ensure it allowVolumeExpansion: true , if it does, eidt it to have this attribute

@leebug: Related to your error "I'm getting an error "could not be patched" when increasing the storage to 70MB", where do you practice this? In your home lab or Udemy Kodekloud labs? Maybe the storage class "Class: csi-hostpath-sc" is not configured in your environment as in the CKA exam.

I'm getting an error "could not be patched" when increasing the storage to 70MB k edit pvc pv-volume --save-config error: persistentvolumeclaims "pv-volume" could not be patched: persistentvolumeclaims "pv-volume" is forbidden: only dynamically provisioned pvc can be resized and the storageclass that provisions the pvc must support resize You can run `kubectl replace -f /tmp/kubectl-edit-777230424.yaml` to try this update again.

I have notice, PV was not created In the exam, without PV how can we create PVC directly ?