<p>I created a persistent volume using the following YAML</p>

<pre><code>apiVersion: v1
kind: PersistentVolume
metadata:
  name: dq-tools-volume
  labels:
    name: dq-tools-volume
spec:
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Recycle
  storageClassName: volume-class
  nfs:
    server: 192.168.215.83
    path: "/var/nfsshare"
</code></pre>

<p>After creating this I created  two persistentvolumeclaims  using following YAMLS</p>

<p><strong>PVC1:</strong></p>

<pre><code>apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: jenkins-volume-1
  labels:
    name: jenkins-volume-1
spec:
  accessMOdes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 3Gi
  storageClassName: volume-class
  selector:
    matchLabels:
      name: dq-tools-volume
</code></pre>

<p><strong>PVC2:</strong></p>

<pre><code>apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: jenkins-volume-2
  labels:
    name: jenkins-volume-2
spec:
  accessMOdes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 3Gi
  storageClassName: volume-class
  selector:
    matchLabels:
      name: dq-tools-volume
</code></pre>

<p>But i noticed that both of these persistent volume claims are writing to same backend volume.</p>

<p>How can i isolate data of one persistentvolumeclaim from another. I am using this for multiple installations of Jenkins. I want workspace of each Jenkins to be isolated.</p>

<p>As @D.T. explained a persistent volume claim is exclusively bound to a persistent volume.<br>
<strong>You cannot bind 2 pvc to the same pv</strong>.</p>

<p><a href="https://stackoverflow.com/questions/44204223/kubernetes-nfs-persistent-volumes-multiple-claims-on-same-volume-claim-stuck">Here</a> you can find another case where it was discussed. </p>

<p>There is a better solution for your scenario and it involves using  <a href="https://github.com/helm/charts/tree/master/stable/nfs-client-provisioner" rel="nofollow noreferrer">nfs-client-provisioner</a>. To achive that, firstly you have to install helm in your cluster an than follow these steps that I created for a previous <a href="https://serverfault.com/questions/990520/nfs-server-and-client-are-working-but-data-is-not-on-the-server/990621#990621">answer</a> on ServerFault. </p>

<p>I've tested it and using this solution you can isolate one PVC from the other. </p>

<p><strong>1 - Install and configur NFS Server on my Master Node (Debian Linux, this might change depending on your Linux distribution):</strong></p>

<p>Before installing the NFS Kernel server, we need to update our system’s repository index:</p>

<pre><code>$ sudo apt-get update
</code></pre>

<p>Now, run the following command in order to install the NFS Kernel Server on your system:</p>

<pre><code>$ sudo apt install nfs-kernel-server
</code></pre>

<p>Create the Export Directory</p>

<pre><code>$ sudo mkdir -p /mnt/nfs_server_files
</code></pre>

<p>As we want all clients to access the directory, we will remove restrictive permissions of the export folder through the following commands (this may vary on your set-up according to your security policy):    </p>

<pre><code>$ sudo chown nobody:nogroup /mnt/nfs_server_files
$ sudo chmod 777 /mnt/nfs_server_files
</code></pre>

<p>Assign server access to client(s) through NFS export file</p>

<pre><code>$ sudo nano /etc/exports
</code></pre>

<p>Inside this file, add a new line to allow access from other servers to your share.</p>

<pre><code>/mnt/nfs_server_files        10.128.0.0/24(rw,sync,no_subtree_check)
</code></pre>

<p>You may want to use different options in your share. 10.128.0.0/24 is my k8s internal network.</p>

<p>Export the shared directory and restart the service to make sure all configuration files are correct. </p>

<pre><code>$ sudo exportfs -a
$ sudo systemctl restart nfs-kernel-server
</code></pre>

<p>Check all active shares: </p>

<pre><code>$ sudo exportfs
/mnt/nfs_server_files
                10.128.0.0/24
</code></pre>

<p><strong>2 - Install NFS Client on all my Worker Nodes:</strong></p>

<pre><code>$ sudo apt-get update
$ sudo apt-get install nfs-common
</code></pre>

<p>At this point you can make a test to check if you have access to your share from your worker nodes: </p>

<pre><code>$ sudo mkdir -p /mnt/sharedfolder_client
$ sudo mount kubemaster:/mnt/nfs_server_files /mnt/sharedfolder_client
</code></pre>

<p>Notice that at this point you can use the name of your master node. K8s is taking care of the DNS here. 
Check if the volume mounted as expected and create some folders and files to male sure everything is working fine. </p>

<pre><code>$ cd /mnt/sharedfolder_client
$ mkdir test
$ touch file
</code></pre>

<p>Go back to your master node and check if these files are at /mnt/nfs_server_files folder. </p>

<p><strong>3 - Install NFS Client Provisioner</strong>.</p>

<p>Install the provisioner using helm:</p>

<pre><code>$ helm install --name ext --namespace nfs --set nfs.server=kubemaster --set nfs.path=/mnt/nfs_server_files stable/nfs-client-provisioner
</code></pre>

<p>Notice that I've specified a namespace for it. 
Check if they are running: </p>

<pre><code>$ kubectl get pods -n nfs
NAME                                         READY   STATUS      RESTARTS   AGE
ext-nfs-client-provisioner-f8964b44c-2876n   1/1     Running     0          84s
</code></pre>

<p>At this point we have a storageclass called nfs-client: </p>

<pre><code>$ kubectl get storageclass -n nfs
NAME         PROVISIONER                                AGE
nfs-client   cluster.local/ext-nfs-client-provisioner   5m30s
</code></pre>

<p>We need to create a PersistentVolumeClaim: </p>

<pre><code>$ more nfs-client-pvc.yaml

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  namespace: nfs 
  name: test-claim
  annotations:
    volume.beta.kubernetes.io/storage-class: "nfs-client"
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Mi
</code></pre>

<pre><code>$ kubectl apply -f nfs-client-pvc.yaml
</code></pre>

<p>Check the status (Bound is expected):</p>

<pre><code>$ kubectl get persistentvolumeclaim/test-claim -n nfs
NAME         STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
test-claim   Bound    pvc-e1cd4c78-7c7c-4280-b1e0-41c0473652d5   1Mi        RWX            nfs-client     24s
</code></pre>

<p><strong>4 - Create a simple pod to test if we can read/write out NFS Share:</strong></p>

<p>Create a pod using this yaml: </p>

<pre><code>apiVersion: v1
kind: Pod
metadata:
  name: pod0
  labels:
    env: test
  namespace: nfs  
spec:
  containers:
  - name: nginx
    image: nginx
    imagePullPolicy: IfNotPresent
    volumeMounts:
      - name: nfs-pvc
        mountPath: "/mnt"
  volumes:
    - name: nfs-pvc
      persistentVolumeClaim:
        claimName: test-claim
</code></pre>

<pre><code>$ kubectl apply -f pod.yaml
</code></pre>

<p>Let's list all mounted volumes on our pod:</p>

<pre><code>$ kubectl exec -ti -n nfs pod0 -- df -h /mnt
Filesystem                                                                               Size  Used Avail Use% Mounted on
kubemaster:/mnt/nfs_server_files/nfs-test-claim-pvc-a2e53b0e-f9bb-4723-ad62-860030fb93b1   99G   11G   84G  11% /mnt
</code></pre>

<p>As we can see, we have a NFS volume mounted on /mnt. (Important to notice the path <code>kubemaster:/mnt/nfs_server_files/nfs-test-claim-pvc-a2e53b0e-f9bb-4723-ad62-860030fb93b1</code>) </p>

<p>Let's check it: </p>

<pre><code>root@pod0:/# cd /mnt
root@pod0:/mnt# ls -la
total 8
drwxrwxrwx 2 nobody nogroup 4096 Nov  5 08:33 .
drwxr-xr-x 1 root   root    4096 Nov  5 08:38 ..
</code></pre>

<p>It's empty. Let's create some files: </p>

<pre><code>$ for i in 1 2; do touch file$i; done;
$ ls -l 
total 8
drwxrwxrwx 2 nobody nogroup 4096 Nov  5 08:58 .
drwxr-xr-x 1 root   root    4096 Nov  5 08:38 ..
-rw-r--r-- 1 nobody nogroup    0 Nov  5 08:58 file1
-rw-r--r-- 1 nobody nogroup    0 Nov  5 08:58 file2
</code></pre>

<p>Now let's where are these files on our NFS Server (Master Node): </p>

<pre><code>$ cd /mnt/nfs_server_files
$ ls -l 
total 4
drwxrwxrwx 2 nobody nogroup 4096 Nov  5 09:11 nfs-test-claim-pvc-4550f9f0-694d-46c9-9e4c-7172a3a64b12
$ cd nfs-test-claim-pvc-4550f9f0-694d-46c9-9e4c-7172a3a64b12/
$ ls -l 
total 0
-rw-r--r-- 1 nobody nogroup 0 Nov  5 09:11 file1
-rw-r--r-- 1 nobody nogroup 0 Nov  5 09:11 file2
</code></pre>

<p>And here are the files we just created inside our pod! </p>
