I am testing out something with the PV and wanted to get some clarification. We have an 18 node cluster(using Docker EE) and we have mounted NFS share on each of this node to be used for the k8s persistent storage. I created a PV (using hostPath) to bind it with my nginx deployment(mounting the /usr/share/nginx/html to PV).
apiVersion: v1
kind: PersistentVolume
metadata:
name: nfs-test-namespace-pv
namespace: test-namespace
spec:
storageClassName: manual
capacity:
storage: 2Gi
accessModes:
- ReadWriteMany
hostPath:
path: "/nfs_share/docker/mynginx/demo"
How to create the PVC:
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: nfs-test-namespace-pvc
namespace: test-namespace
spec:
storageClassName: manual
accessModes:
- ReadWriteMany
resources:
requests:
storage: 2Gi
Deployment File:
apiVersion: apps/v1
kind: Deployment
metadata:
name: mynginx
specs:
selector:
matchLabels:
run: mynginx-apps
replicas:2
template:
metadata:
labels:
run: mynginx-apps
spec:
volumes:
- name: task-pv-storage
persistentVolumeClaim:
claimName: nfs-test-namespace-pvc
containers:
- name: mynginx
image: dtr.midev.spglobal.com/spgmi/base:mynginx-v1
ports:
- containerPort: 80
name: "http-server"
volumeMounts:
- mountPath: "/usr/share/nginx/html"
name: task-pv-storage
So i assume when my pod starts the default index.html file from the nginx image should be available at the /usr/share/nginx/html within my pod and it should also be copied/available at my /nfs_share/mynginx/demo.
However i am not seeing any file here and when i expose this deployment and access the service it gives me 403 error as the index file is not available. Now when i create an html file either from inside the pod or from the node on the nfs share mounted as PV, it works as expected.
Is my assumption of the default file getting copied to hostpath correct? or am i missing something?
Your /nfs_share/docker/mynginx/demo
will not be available in pod
, explanation is available here:
apiVersion: v1
kind: PersistentVolume
metadata:
name: task-pv-volume
labels:
type: local
spec:
storageClassName: manual
capacity:
storage: 10Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/mnt/data"
The configuration file specifies that the volume is at
/mnt/data
on the cluster’s Node. The configuration also specifies a size of 10 gibibytes and an access mode ofReadWriteOnce
, which means the volume can be mounted as read-write by a single Node. It defines the StorageClass namemanual
for the PersistentVolume, which will be used to bind PersistentVolumeClaim requests to this PersistentVolume.
You do not see PV
on your pod
, it's being used to utilize as PVC
which then can be mounted inside a pod
.
You can read the whole article Configure a Pod to Use a PersistentVolume for Storage which should answer all the questions.