PV file not saved on host - kubernetes

Question

hi all quick question on host paths for persistent volumes
I created a PV and PVC 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"
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: task-pv-claim
spec:
storageClassName: manual
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 3Gi
and I ran a sample pod
apiVersion: v1
kind: Pod
metadata:
name: task-pv-pod
spec:
volumes:
- name: task-pv-storage
persistentVolumeClaim:
claimName: task-pv-claim
containers:
- name: task-pv-container
image: nginx
ports:
- containerPort: 80
name: "http-server"
volumeMounts:
- mountPath: "/usr/share/nginx/html"
name: task-pv-storage
i exec the pod and created a file
root#task-pv-pod:/# cd /usr/share/nginx/html
root#task-pv-pod:/usr/share/nginx/html# ls
tst.txt
However, when I go back to my host and try to ls the file , its not appearing. Any idea why? My PV and PVC are correct as I can see that it has been bounded.
ubuntu#ip-172-31-24-21:/home$ cd /mnt/data
ubuntu#ip-172-31-24-21:/mnt/data$ ls -lrt
total 0

Answer 1

A persistent volume (PV) is a kubernetes resource which has its own lifecycle independent of the pod pv documentation. Using a PVC to consume from a PV makes it visible in some other tool. For example azure files, ELB, a server with NFS, etc. My point here is that there is no reason why the PV should exist in the node.
If you want your persistence to be saved in the node use the hostPath option for PVs. Check this link. Though this is not a good production practice.

Answer 2

First of all, you don't need to create a PV if you are creating a PVC. PVCs create PV, if you have the right storageClass.
Second, hostPath is one delicate PV in Kubernetes world. That's the only PV that doen't need to be created to be mounted in a Pod. So you could have not created neither PV nor PVC and a hostPath volume would work just fine.
To make a test, delete your PV and PVC, and create your Pod like this:
apiVersion: v1
kind: Pod
metadata:
name: nginx-volume
labels:
app: nginx
spec:
containers:
- image: nginx
name: nginx
securityContext:
privileged: true
ports:
- containerPort: 80
name: nginx-http
volumeMounts:
- name: nginx
mountPath: /root/nginx-volume # path in the pod
volumes:
- name: nginx
hostPath:
path: /var/test # path in the host machine
I know this is a confusing concept, but that's how it is.