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-   -   USB drive not working properly, read only device? (USB key storage device) (

Arodef 07-14-2004 06:52 PM

USB drive not working properly, read only device? (USB key storage device)
I'm using Fedora Core 1. I configured my system to work with the usb key by adding the following to /etc/fstab:

/dev/sda1 /mnt/usbkey auto defaults,noauto,user 0 0

However the device is very flaky. I can read from it fine, however when I try to write to the card I get a message saying the "destination disk is read-only." This usually occurs after I've already written data to the usbkey. But once it happens, it seems I can never write to it again.

As a workaround I've been formatting the card in Windows to fat16, and then I'm able to write to the usb drive again until the read only problem happens again. What is the command to format the usb drive in linux? I wold like to use FAT so I can use the usbkey in both Windows and Linux. Thanks.

kilgoretrout 07-14-2004 09:31 PM

Try changing your fstab entry to this:

/dev/sda1 /mnt/usbkey vfat umask=0,user,iocharset=iso8859-1,codepage=850,noauto,quiet 0 0

For formatting the device in linux, open a console and as root run:

# mkfs -t msdos /dev/sda1

feight 06-01-2006 09:18 PM

Holy hand-grenade... thank you so very much. I had been trying to figure out how to make my 60GB iAudio X5 MP3 player work in linux since I had to reformat it.
I couldn't format it with anything but NTFS in Windows XP because XP will not let you format anything with more than 32GB of storage with anything else. I found Swissknife and used that... only to find that it worked but was using a variation of FAT that was not readable in Linux...

bsurfin 10-11-2006 12:39 AM

Question, I have Slackware 10.2 and the 2.4.31 kernal, I even have my usb printer & Scanner working, Would
"/dev/sda1 /mnt/usbdrive vfat umask=0,user,iocharset=iso8859-1,codepage=850,noauto,quiet 0 0"
also work to setup a usb hard drive, and is that all I need to do to setup the device ? or what would you recommend ?

kilgoretrout 10-11-2006 11:57 AM

/dev/sda1 should correspond to the device file for the FAT32 partition you are mounting on your usb hard drive. That's usually the case, but not always. For example, if you have a sata drive with a primary partition, that would be sda1, not you usb hard drive. In that case, your first primary partition on the usb drive would probably be sdb1. It really depends on how your system is set up hardware wise and how the external drive is partitioned. You also have to have the proper modules loaded to detect a usb mass storage device. I believe they are loaded automatically in slack 10.2.

To check all this out is pretty easy. With the external hard drive not turned on, open a console and as root run:

# fdisk -l

That will list all the partitions that your system recognizes whether mounted or not. Now connect and turn on your external usb hard drive. Give it a moment to spin up and rerun:

# fdisk -l

You should see the new printout for your external hard drive which will list the partition structure and device file designation for the drive. If not, post back; you probably don't have the necessary usb/scsi modules loaded. If you do see it, you can adapt the line I gave to correspond to the device file you want to mount on the external hard drive.

bsurfin 10-11-2006 11:03 PM

I did fdisk -l just like you said, and it was there /dev/sda1 .
I added "/dev/sda1 /mnt/usbdrive vfat umask=0,users,iocharset=iso8859-1,codepage=850,noauto,quiet 0 0" to the fstab and I got an error message, something like /mnt/usbdrive does not exist, so I clicked on the /mnt directory, right clicked, created a new folder, renamed it usbdrive, I went back to system icon and clicked, and vioala it now works great, I tweaked permissions and It is now working perfectly !

Thanks for the help guys...

bsurfin 10-12-2006 09:22 AM

As for the DVD+rw, it does not have an sda#, what would you suggest for that ?

Xerop 10-12-2006 11:33 AM

use fat32 if possible I know both linux and windows support it.
fat in general is not a very stable system so properly dismount it after use.

kilgoretrout 10-13-2006 09:38 AM


As for the DVD+rw, it does not have an sda#, what would you suggest for that ?
Not sure what you want or what your problem is. You may want to start a new thread as this one is two years old. The fstab entry for a cdrom or dvd writer in slackware usually looks like this:

/dev/hd* /mnt/cdrom auto noauto,user,ro 0 0

where "hd*" corresponds to the device file for the drive.

bsurfin 10-13-2006 08:44 PM

That helps, thank you...

firemankurt 05-05-2008 01:10 PM

USB drive mounts readonly
One of my USB drives started mounting read only no matter the system settings in kubuntu.


fdisk -l
found that the partition table got messed up.

Partition 1 has different physical/logical endings
Backed up drive

reformated as FAT 32

Now work fine.

Hope this helps someone.

michaelk 12-31-2009 11:21 PM

I have reported your posts to be moved to their own thread. Its best to start a new thread instead of posting a reply to an old one which is really unrelated to yours. Some flash drives like Imations are not partitioned and do not have a MBR or partition table. I own a couple of them and the output of fdisk -l looks basically the same. You should be able to mount the drive using /dev/sdc instead of /dev/sdc1. Is your drive automounting but it is read only?

cdarrah010 01-01-2010 07:53 AM

I probably will have to repartition it.... How would i go about doing such a thing?

And yes it will automatically mount without having to touch the terminal

repo 01-01-2010 07:55 AM


I probably will have to repartition it.... How would i go about doing such a thing?
You can use gparted, should be included in your distro

cdarrah010 01-01-2010 08:32 AM

i try to reformat to fat32 in gparted by clicking delete partition, then hitting New, clicking fat32 for the filesystem and hitting create. i get a error stating that it

could not create new fat32 file system >
mkdosfs -f32 -v -n "" /dev/sdc1
mkdosfs 3.0.3 (18 May 2009)
mkdosfs: unable to open /dev/sdc1

which i don't know why it would want to open it because it was just deleted by the system... I feel a little bit like windows was designed for noobs like

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