How to visit U disk?

Polytropon freebsd at
Thu Aug 14 14:47:53 UTC 2008

On Thu, 14 Aug 2008 08:39:43 +0800, EdwardKing <zhangsc at> wrote:
> Then I use dmesg:
> $dmesg | grep ^da
> da0 at umass-sim0 bus 0 target 0 lun 0
> da0:<USB NAND FLASH DISK 0.20> Removable Direct Access SCSI-2 device
> da0:1.000MB/s transfers
> da0:125MB (256000 512 byte sectors: 64H 32S/T 125C)

Correct, this shows da0 is your USB disk. You just need to know
which partition to access.

	# ls /dev/da0*

will show you which entries are present. As I mentioned before,
/dev/da0s1 or /dev/da0s1c should be the correct one.

You can check which partitions are on da0 with this command
that just does some reading (no modification):

	# fdisk da0

Then you tried, as suggested:

> $mount -t msdosfs dev/da0s1c /mnt
> mount_msdosfs: /dev/da0s1c: Operation not permitted

Yes, of course. You're issuing this command from a user's shell,
not as root. But because of FreeBSD's security concepts, you need
to do the mount operation as root (that's why I prefixed the
mount command with a # sign), so use "su" or "sudo" (sudo needs
to be installed).

You can, of course, enable the user to have access to the USB
devices by modifying /etc/devfs.conf and setting vfs.usermount=1
in /etc/sysctl.conf.

> $mount -t msdosfs dev/da0 /mnt
> mount_msdosfs: /dev/da0: Operation not permitted

Same reason here. You need to be root to do this. And don't
complain, it's completely intended to be this way. :-)

>From Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

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