Mounting of USB sticks (not formatted as FAT32/NTFS)

milomak · 11-08-2009, 11:21 AM

I mostly format them as FAT32 or NTFS. So when I insert them, most DEs will pop up a box to mount the volume (or can be done from a file manager directly). In any event the normal user can read/write.

I've noticed that when the stick is formatted as ext3/4, reiserfs etc, that read/write is possible only as root.

I realise one of the options would be to add an entry in fstab, but I think this would remove the ability for all sticks to be mounted as /media/<format label>. What other options are there?

Mr-Bisquit · 11-08-2009, 01:36 PM

When you mount the disk again, set permissions to 0666.

Code:

# chmod 0666 /path/to/dev/usbstick

j1alu · 11-09-2009, 12:28 AM

Quote:

I've noticed that when the stick is formatted as ext3/4, reiserfs etc, that read/write is possible only as root.

i aint got that problem. but my wm (e17, fluxbox...) doesnt do automounting the way you described (might be one may set it that way, for me it doesnt).

therefor i dont think much about it an am not that sure bout the following "internals" of mounting:
user is member of plugdev?
you have tried pmount?
have you tried mounting it in the users /home-directory?
making an entry in fstab, commenting it out and mounting the ext3/ext4 usb-stick after uncommenting the line with mount -a would be an option/possible at all?

for following posts you might tell which OS and which window-manager/desktop-environment you are using.

milomak · 11-09-2009, 12:21 PM

The usb stick was formatted with: mkfs.ext4 -L label /dev/sdd (tried it both in Fedora and Arch Linux)

I've tried on:

Laptop - Debian Sid (32-bit) and Gnome (Automount)
Desktop - Debian Sid (64-bit) and KDE (Click the File Manager icons that appears)
Desktop - Arch Linux (64-bit) and KDE (Click the File Manager icons that appears)
Desktop - Fedora 12 Beta (64-bit) and KDE (Click the File Manager icons that appears)
MythTV - Debian Testing (32-bit) and Gnome (Automount)

In all of them, after it mounts, a non-root user cannot write to it. And cannot read files that are copied onto the stick by root.

chmod 0666 /dev/device did not work.

DavidMcCann · 11-09-2009, 12:28 PM

I use ext2 (not ext3) with no trouble and no fstab entry. But previously, when I used the default MS formating, I often had a read-only mount occurring: this was always due to some fault having developed in the filing system. So, try fsck and see if that helps.

milomak · 11-09-2009, 02:06 PM

i doubt very much its an fsck related thing, as this will happen as soon after i have formatted the stick.

arubin · 11-10-2009, 09:23 AM

I have the same issue using ext3 formatted usb drives.

What I generally do is create folders as root on the usb drive and chown or chmod them to allow the user to write to the folder.

I guess that there would be another way around it using a udev rule to mount the drive to a specific folder but I have not tried that.

lewc · 11-10-2009, 05:35 PM

content removed

milomak · 11-12-2009, 02:34 PM

you did see that the same problem happens in Arch and Fedora 12 right?

lewc · 11-12-2009, 05:32 PM

content removed

milomak · 11-13-2009, 01:35 PM

glad i could be of assistance. if you pay for travel costs, food and lodging you can gladly have me around with you all day.

You may also be happy to learn that the same thing is happening when using OpenSuse 11.2

lewc · 11-13-2009, 02:40 PM

content removed

milomak · 11-14-2009, 06:47 AM

Now I like to consider myself as an accomodating kind of guy. So i thought I would go looking for this LiveCD for the distro called "in a god damn". I trawled the internet without much luck. So eventually I settled on a PCLinuxOS LXDE LiveCD (I hope this will not be an issue for you).

So I put that stick in. Fired up the LXDE file mananger (pcmanfm). It recognised it. Clicked on it. It showed the files on the stick. Tried to copy a file onto it. No go.

So then I did the following while in the LiveCD environment

[root@localhost guest]# mkfs.ext3 /dev/sdd -L euroTEK

Code:

mke2fs 1.41.6 (30-May-2009)
/dev/sdd is entire device, not just one partition!
Proceed anyway? (y,n) y
Filesystem label=euroTEK
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
62976 inodes, 251904 blocks
12595 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=260046848
8 block groups
32768 blocks per group, 32768 fragments per group
7872 inodes per group
Superblock backups stored on blocks: 
	32768, 98304, 163840, 229376

Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 20 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

[root@localhost guest]# exit
[guest@localhost ~]$ cd /media/euroTEK/
[guest@localhost euroTEK]$ echo "Test" > test.txt

Quote:

bash: test.txt: Permission denied

[guest@localhost euroTEK]$ uname -a

Quote:

Linux localhost 2.6.26.8.tex3 #1 SMP Mon Jan 12 04:33:38 CST 2009 i686
Intel(R) Core(TM) i7 CPU 920 @ 2.67GHz GNU/Linux

[guest@localhost euroTEK]$ ls

Quote:

lost+found/

lewc · 11-14-2009, 08:30 AM

content removed

tredegar · 11-14-2009, 12:38 PM

My ext3 USB disk automounts just fine. It always has done, with every distro I've used.

Quote:

The usb stick was formatted with: mkfs.ext4 -L label /dev/sdd

This is a strange way to format a linux disk. And your choice of label is bad - it might not always be /dev/sdd so use a better label like Disgo or USB16GB to avoid future confusion.

You really should partition it first with fdisk /dev/sdwhatever , make one partition, using the whole disk space if you like.

Then format it: mkfs.ext4 -L label /dev/sdwhatever1

Windows (FAT32 / ntfs) doesn't seem to mind if the disk is partitioned or not. Linux does.