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Quick summary: How can I arrange for USB FAT32 thumb drives to be auto-mounted as /media/USER/LABEL, with non-root read/write permissions?

(There are a lot of questions here about automounting USB drives, but I don't see one that's directly relevant.)

I'm running 14.04.4 LTS on an x86_64 system. I'm using the Cinnamon desktop if that matters. I have a FAT32-formatted USB thumb drive. I've run fsck on the drive, and it shows no errors.

Until recently, when I inserted the drive into a USB port it would not auto-mount. It would show up in the output of lsusb, as:

Bus 001 Device 008: ID 058f:6387 Alcor Micro Corp. Flash Drive

I was able to mount it manually, using something like:

sudo mkdir /tmp/usb ; sudo mount /dev/sdg1 /tmp/usb

but that was less than ideal.

I recently installed the usbmount package. After that (and a reboot), when I insert the drive it automatically mounts as /media/usb0:

$ df /media/usb0
Filesystem     1K-blocks  Used Available Use% Mounted on
/dev/sdg1       15712248  9080  15703168   1% /media/usb0
$

The problem: I can read everything on the drive, but it all appears to be owned by root and I can't write to the drive without using sudo or equivalent.

What I want to happen is this: When I insert the drive, it's automatically mounted as /media/username/label, where username is my user name and label is the volume label on the drive -- and all files on the drive are owned and writable by my account.

This used to happen automatically, but I don't know how I set it up. Some time ago, I upgraded my workstation from Debian 6 to Ubuntu 14.04. I had the auto-mounting worked the way I want it when I was running Debian 6. I was also using a different desktop environment (some version of Gnome, perhaps?). (The transition from Debian 6 to Ubuntu 14.04 happened to coincide with me not using USB drives as much; now I need to start using them again, so I haven't tried this in a while.)

Keith Thompson
  • 1,345

2 Answers2

1

I think I've figured out what happened.

I had installed a package called usbmount. With that package installed, inserting a USB drive would automatically mount it as something like /media/usb0, with everything on the drive owned by root. (This is for a drive with a FAT32 filesystem, which for various reasons is what I need to use. I don't know how it would work with a filesystem that actually supports file ownership.)

I've since uninstalled the usbmount. Now when I insert a USB thumb drive, it isn't automatically mounted -- but it does show up in the GUI file manager. (I use the Cinnamon desktop, so my GUI file manager is Nemo; Nautilus does the same thing.) It appears as an entry in the left column, labeled "16 GB Volume"). If I then double-click on that, it's then mounted as, for example, /media/kthompson/EC1C-4374. And if I then use gparted to set the drive's label to THUMB, it's mounted as /media/kthompson/THUMB, which is exactly what I want.

It's likely I didn't notice this because I don't use the GUI file manager very often, and that I incorrectly remembered it being mounted automatically.

It would be nice to have the drive mounted under /media/$USER automatically, but opening a GUI file manager and double-clicking an icon isn't much of a burden. And if it were mounted automatically, it's probably not 100% clear which user should own it; that's probably why usbmount mounts it as root.

Keith Thompson
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-1

Possible answer:

I'm not sure how to do this for all USB drives universally, but if you have specific drives, you can edit /etc/fstab to set up their mounts how you like them. You can use Disks (gnome-disks), or if you don't mind getting your hands dirty, you can edit it manually. You'll want to set a <mount point> and I think you'll want these options:

uid=1000,gid=1000,dmask=022,fmask=022,users

Run man fstab for more info. There's also some info here on the community wiki.

wjandrea
  • 14,504