Lab 9.3 Create a Persistent Volume Claim - permissions issue
 
            I've just completed this lab and think I get it but I thought I'd try out writing to the hello.txt file pre-created on the volume from a container running on two different nodes.  I found that it was not possible to write to the pre-created hello.txt file due to a permissions error.kubectl exec nginx-nfs-76d96bcdb-s7lpl -c nginx -- /bin/bash -c "echo 'changed by s7lpl' >> /opt/hello.txt" /bin/bash: line 1: /opt/hello.txt: Permission denied
I found however that I could create a file from one of the containers and the write to it from bothkubectl exec nginx-nfs-76d96bcdb-x4thj -c nginx -- /bin/bash -c "echo 'x4thj change' > /opt/s7lplfile.txt" kubectl exec nginx-nfs-76d96bcdb-s7lpl -c nginx -- /bin/bash -c "cat /opt/s7lplfile.txt"                   x4thj change
Change from other container on other nodekubectl exec nginx-nfs-76d96bcdb-s7lpl -c nginx -- /bin/bash -c "echo 's71pl change' >> /opt/s7lplfile.txt"
File has now been changed by both containerskubectl exec nginx-nfs-76d96bcdb-s7lpl -c nginx -- /bin/bash -c "cat /opt/s7lplfile.txt"                    x4thj change s71pl change
NFT exports on CPlab1cp1:~$ cat /etc/exports /opt/sfw/ *(rw,sync,no_root_squash,subtree_check)
hello file permissionslab1cp1:~$ ls -l /opt/sfw/hello.txt -rw-rw-rw- 1 samfraser samfraser 32 Sep 18 16:13 /opt/sfw/hello.txt
PVlab1cp1:~$ kubectl get pv lab1pvvol-1 -o yaml apiVersion: v1 kind: PersistentVolume metadata:   annotations:     pv.kubernetes.io/bound-by-controller: "yes"   creationTimestamp: "2025-09-18T13:18:23Z"   finalizers:   - kubernetes.io/pv-protection   name: lab1pvvol-1   resourceVersion: "781741"   uid: 48a9c3e4-2780-4527-99c0-4d667b335b3b spec:   accessModes:   - ReadWriteMany   capacity:     storage: 20Mi   claimRef:     apiVersion: v1     kind: PersistentVolumeClaim     name: lab1pvc-one     namespace: default     resourceVersion: "781739"     uid: 88b6ffac-662a-4136-a9b6-bb771a3dd6da   nfs:     path: /opt/sfw     server: lab1cp   persistentVolumeReclaimPolicy: Retain   volumeMode: Filesystem
PVClab1cp1:~$ kubectl get pvc lab1pvc-one -o yaml apiVersion: v1 kind: PersistentVolumeClaim metadata:   annotations:     pv.kubernetes.io/bind-completed: "yes"     pv.kubernetes.io/bound-by-controller: "yes"   creationTimestamp: "2025-09-18T13:38:12Z"   finalizers:   - kubernetes.io/pvc-protection   name: lab1pvc-one   namespace: default   resourceVersion: "781743"   uid: 88b6ffac-662a-4136-a9b6-bb771a3dd6da spec:   accessModes:   - ReadWriteMany   resources:     requests:       storage: 10Mi   volumeMode: Filesystem   volumeName: lab1pvvol-1
Pod spec (relevant stuff)spec:         volumeMounts:         - mountPath: /opt           name: nfs-vol       securityContext:         fsGroup: 1000       volumes:       - name: nfs-vol         persistentVolumeClaim:           claimName: lab1pvc-one
As you can see I've tried to add security Context with the same group as the file on the cp but that didn't make any difference, any ideas?
Comments
- 
            Hi @dsfraser, Did you set the permission on /opt/sfw/as instructed in step 2 of lab exercise 9.2?Regards, 
 -Chris0
- 
            yes I have 
 ls -l /opt/
 drwxrwxrwt 3 root root 4096 Sep 25 19:54 sfw0
- 
            Hi @dsfraser, I just went through the exercise and I was not able to reproduce the issue. I used the hello.txtfile created as instructed in step 2 of lab 9.2 and anew.txtfile created by one of the pods. They both have the same permissions and eachechoattempt succeeds from either one of the pod replicas of thenginx-nfsdeployment.Permissions of /opt/sfw:student@cp:~$ ls -la /opt/ drwxrwxrwt 2 root root 4096 Oct 10 17:12 sfw/ Permissions of the 2 files in /opt/sfwverified from thecpnode:student@cp:~$ ls -la /opt/sfw/ -rw-r--r-- 1 root root 9 Oct 10 17:14 hello.txt -rw-r--r-- 1 root root 34 Oct 10 18:38 new.txt Permissions of the 2 files verified from one of the nginx-nfspod replicas:student@cp:~$ kubectl exec nginx-nfs-59d684b459-cmb6h -- /bin/bash -c "ls -la /opt" -rw-r--r-- 1 root root 29 Oct 10 18:25 hello.txt -rw-r--r-- 1 root root 48 Oct 10 18:41 new.txt Are there any permission restrictions in your manifest? Regards, 
 -Chris0
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