How to extend PVC. #Kubernetes #Openshift

pvc-resizing.txt

## How to extend a PV:

pvcname=pvc60
volumename=volume60
mountpath=/opt/app-root/src/mount60

# Deploy a test app
oc new-app --template=openshift/httpd-example --name=app01

# Create a PVC
cat << EOF | oc create -f -
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: $pvcname
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 4Gi
  storageClassName: block-default-storage-class
  volumeMode: Filesystem
EOF

# mount volume through the console:
Action > Add storage > use existing claim
Mountpath : $mountpath
Save

# create a test file in the volume
oc get pods
podname=app01-4-47pkc
oc exec $podname -- bash -c "echo test > $mountpath/webpage.html »

# verify the file before expanding the size
oc get route
route=httpd-example
oc patch route/$route -p '{"spec":{"tls":{"termination":"edge"}}}'
route=$(oc get route $route -o=jsonpath='{.spec.host}')
curl -s  -L https://$route/mount60/webpage.html
 >> test

oc exec $podname -- df -h $mountpath

# Scale down the deployment to 0 in order to resize the volume
 #note the replica number to reset it as it was.
oc get dc
oc scale dc/httpd-example --replicas=0

# Expand hth volume
oc get pvc
oc patch pvc $pvcname --type=merge -p '{"spec":{"resources":{"requests":{"storage": "5Gi"}}}}’ 

# Scale up the application in order for the pvc to increase
oc scale dc/httpd-example --replicas=1 

# watch pvc change size
watch oc get pvc

#Verify the data is still on the volume after expansion
curl -s  -L https://$route/mount60/webpage.html
 >> test