Can't write to an external USB drive with Turnkey Fileserver (CT)


New Member
Aug 1, 2023
I'm at my witts end. I've tried everything.

I have an SSD USB Drive that I've connected to Proxmox. I need 1-2 containers and 1 VM to be able to view/write to it.

I edited fstab to include the line:
UUID=B2A9-0D71 /media/FS_Drive exfat defaults,noatime,nofail 0 2
Then ran mount -a

I then did ls and saw the folders/files on the USB drive.

Then, after installing Turnkey Fileserver, I went to /etc/pve/lxc/ and edited 103.conf to include:
mp0: /media/FS_Drive,mp=/USB_Drive

I then started the fileserver and could see the USB_Drive folder and the contents. But the folders all had "nobody" ownership and I couldn't save to it.

The weird thing is that in shell on Proxmox, I could go to the /media/FS_Drive and type touch hello and see the file get made.

But I need the fileserver to write to it, so I found this instructions on making the folder writeable.

As per the instructions, I went back into 103.conf and added the lines:
# uid map: from uid 0 map 1005 uids (in the ct) to the range starting 100000 (on the host), so 0..1004 (ct) → 100000..101004 (host) lxc.idmap = u 0 100000 1005 lxc.idmap = g 0 100000 1005 # we map 1 uid starting from uid 1005 onto 1005, so 1005 → 1005 lxc.idmap = u 1005 1005 1 lxc.idmap = g 1005 1005 1 # we map the rest of 65535 from 1006 upto 101006, so 1006..65535 → 101006..165535 lxc.idmap = u 1006 101006 64530 lxc.idmap = g 1006 101006 64530

Then I did nano /etc/subuid and nano /etc/subgid and they now both look like this:
root:100000:65536 root:1005:1

Then I tried chown -R 1005:1005 /media/FS_Drive as well as chown 777 /media/FS_Drive and got "operation not permitted". I tried rebooting Proxmox and the chown commands are still not working on that folder, nor can the Fileserver write to that folder.

What am I doing wrong?


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