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I have an external USB drive which my system recognizes as /dev/sdb1. I want to have it automounted with 755 permissions on boot and shared over the network with samba. I created the mount point /mnt/mybook for it, and I've mounted it manually with no problems. If I do mount /dev/sdb1 /mnt/mybook, it mounts correctly and I can access the contents.

I figured this would be simple enough, so I read up on fstab and came up with the following line for it:

UUID=C252-9CA3 /mnt/mybook vfat defaults,mode=755 0 0

I got the UUID from blkid.

When I reboot, the drive is not automounted, much less with the 755 permissions I want. How can I make it so the drive gets correctly automounted with the desired permissions?

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up vote 3 down vote accepted

You could try an alternate approach, which is to recognize your device at the udev level and use /dev/mybook-partition in /etc/fstab. Put something like the following in /etc/udev/rules.d/dwilliams.rules:

KERNEL=="sd*", PROGRAM=="/sbin/blkid %N", RESULT=="C252-9CA3", SYMLINK+="mybook-partition"

The section on Auto mounting USB devices in the Arch wiki for udev might help you further.

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This is better since you might possibly boot the system without the drive attached and if I remember correctly you get dumped in to single-user mode. – LawrenceC Feb 26 '11 at 13:10

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