Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I'm trying to set up a Raspberry Pi to run BitTorrent Sync to back up my files to an external hard drive, but I'm running into some frustrating issues.

First, I need to set up the USB hard drive to auto-mount on boot, because the power frequently goes out where I live. So, I added a line to /etc/fstab

/dev/sda1   /media/josiah    vfat    defaults   0   0

I rebooted, and it mounted the drive, but then btsync couldn't write to it. So, I did a little reading and found that you have to specify the user option, so I tried this;

/dev/sda1   /media/josiah    vfat    defaults,user   0   0

That didn't seem to work either, so I tried specifying all of the defaults manually

/dev/sda1   /media/josiah    vfat    rw,auto,user,async,suid,dev,exec    0   0

I thought it was working, but then btsync started complaining again that it couldn't write to the drive, and when I tried to unmount it as a normal user it said that only a super user can unmount the drive.

That's confusing to me, since I thought that's what the user option was for. What am I missing, or doing wrong?

share|improve this question
add comment

2 Answers

up vote 5 down vote accepted

You can do a chmod after you mounted the partition, but that wouldn't be persistent accross reboots.

You should try this fstab line:

/dev/sda1   /media/josiah    vfat    user,umask=0000   0   0

Or this mount options:

mount -t vfat -ouser,umask=0000 /dev/sda1 /media/josiah

That will make the mounted partition world readable and writable.

If you need a less permissive setup, you should create a new group and mount as follows:

mount -t vfat -ouser,gid=1010,umask=0007 /dev/sda1 /media/josiah

It assumes your new group's gid is 1010. All users that need access to the mountpoint will need to be added to the new group.

share|improve this answer
    
That fstab line worked. Thank you! –  Josiah Sprague Jul 10 '13 at 4:28
add comment

Edit the permissions for the mount directory.

In your case, chmod 777 /media/josiah ought to do the trick quite nicely.

share|improve this answer
    
Which line should I be using in /etc/fstab to auto mount the drive? –  Josiah Sprague Jul 10 '13 at 3:55
    
Also, that command still isn't allowing me to write to the drive. –  Josiah Sprague Jul 10 '13 at 3:58
    
have you tried mounting the directory manually and attempted a basic copy/write with a standard user? –  Scandalist Jul 10 '13 at 4:02
    
Manually works fine. I'm trying to get it to work automatically on boot. –  Josiah Sprague Jul 10 '13 at 4:04
    
Okay, your fstab looks fine, (Looking at your last example) are you sure the external drive is formatted vfat? –  Scandalist Jul 10 '13 at 4:07
show 2 more comments

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.