Unable to mount an NFS share on Proxmox VE

This is really annoying because I could not mount the NFS export from my darktower NAS. I kept getting the error as shown in the feature image above. The see the text version below.

create storage failed: error during cfs-locked 'file-storage_cfg' operation: mkdir /mnt/pve/darktower_backup/dump: Permission denied at /usr/share/perl5/PVE/Storage/Plugin.pm line 1170. (500)

This is probably a bug in Proxmox 6.3-3. Apparently, if you login via CLI and run the df command, you will see that the NFS share is already mounted and you can also see the size and whatnot. However, in the web UI it is not present. The workaround/resolution that I could find is to login using the Shell (web UI), or SSH-in then unmount the NFS and delete the directory in question. Remount NFS again via web UI. This is how you would unmount the NFS share and remove the directory. In my case, the directory in question is darktower_backup.

umount /mnt/pve/darktower_backup
rmdir /mnt/pve/darktower_backup

At this point, you should be able to use the web UI and mount the NFS share. Go back to the web UI – Datacenter > Storage > Add > NFS and re-mount the NFS again.

Hope this help someone. Cheers!

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3 years ago

A similar error usually happens when you already have an external drive mounted onto /mnt folder directly instead of subfolder like /mnt/externaldrivemounted

So perhaps check lsblk to see all mount points and umount /dev/sdeX to unmount the external drive mounted perhaps as /dev/sdeX, then try disable the storage on GUI and enable it again Datacenter -> storage (untick enable, save and tick enable and save)

2 years ago

I tried this and still get the same error 🙁 Any ideas?

2 years ago

I also had this problem, after a little thought the problem was the rights on my NAS server that I had put in reader only it must give the right to read and write for the share to work.

Would love your thoughts, please comment.x