USB storage devices

[srowe]

Does anybody else have problems accessing USB flash disks etc? The problem is that some devices have bogus partition tables and so you end up with

/dev/sda1
/dev/sda2
/dev/sda3
/dev/sda4

instead of a single

/dev/sda

If I blank the device with dd and create a FS with mkdosfs then it works fine (except for a desktop icon, a bug in mkdesktophdicons).

I've a patch to scanpartitions that makes it work the way I think it should.

[rickenbacherus]

What makes you say the partition table is bogus? Is it not actually there?

I have no trouble accessing USB disks no matter how many partitions they have. I don't use desktop icons myself so I'm not much help there.

[Stephen]

I've a patch to scanpartitions that makes it work the way I think it should.

You should submit it to bugzilla to see if can be included.

[srowe]

What makes you say the partition table is bogus? Is it not actually there?

I have no trouble accessing USB disks no matter how many partitions they have. I don't use desktop icons myself so I'm not much help there.

There are no partitions, just a single FAT FS. The kernel however reports 4 partitions

May 16 09:25:07 macau kernel: SCSI device sda: 128000 512-byte hdwr sectors (66 MB)
May 16 09:25:07 macau kernel: sda: Write Protect is off
May 16 09:25:07 macau kernel: sda: sda1 sda2 sda3 sda4

/proc/partitions shows

major minor #blocks name rio rmerge rsect ruse wio wmerge wsect wuse running use aveq

8 0 64000 sda 122895 45 245880 874940 1025 121855 245760 2596960 0 973410 3471900
8 1 2023554176 sda1 0 0 0 0 0 0 0 0 0 0 0
8 2 1408628884 sda2 0 0 0 0 0 0 0 0 0 0 0
8 3 5 sda3 0 0 0 0 0 0 0 0 0 0 0
8 4 490806906 sda4 0 0 0 0 0 0 0 0 0 0 0

Look at the block counts, I call those bogus.

It isn't just a single device, I have three completely different ones that exhibit the same behaviour.

I guess it's really a kernel issue, it shouldn't consider those partitions as valid.

[srowe]

It looks like the issue is related to SYSLINUX, the devices have a bootable image dd'ed on to them.

It seems that SYSLINUX uses the end of the root sector for code/string storage and this confuses the kernel into enumerating the bogus partitions.

[Francesca]

I tried with knoppix 3.3 and the USB device is not recognized at start-up.

Using knoppix 3.2 the USB device is recognized but I have the problem with the four sda partition none of them mountable.

The usb device is not recognized with 'fdisk -l' but compares together with CD-ROM using 'cdrecord -scanbus'

Please, is there a command or a sequence of command to make the usb device work? I have only a work PC with a signle NTFS partition, so, no other way to use linux apart the live cd-rom version and the usb fat32 drive.

[paradocs]

Hi Francesca,

I like running KNOPPIX from the CD.
I tried the USB sticks but had some problems and
gave up using them for now.
I don't know why knoppix3.3 would be so differnt
but I find that it does give a differnt number to my
second usb CDRW device. I backup and restore files
to and from a second CDRW.

Have you tried cfdisk and a linux partition on your usb drive?
But then you can not read it from windows.

Best Wishes
paradocs

[c_cinq]

paradocs

Posted: Tue Oct 28, 2003 1:41 am
Hi Francesca,

I like running KNOPPIX from the CD.
I tried the USB sticks but had some problems and
gave up using them for now.
I don't know why knoppix3.3 would be so differnt
but I find that it does give a differnt number to my
second usb CDRW device. I backup and restore files
to and from a second CDRW.

how do you mount your usb cdrw? Does K3b recognizes it automatically?

[paradocs]

Hi c_cinq,

KNOPPIX is very good (sorry not perfect) at hardware
detection. A usb CDRW should work just fine when booting
from the KNOPPIX CD. It will be automatically mounted
as /dev/cdrom1 /mnt/cdrom1 if KNOPPIX is on /cdrom.

I find a second CDRW (perhaps a DVDRW is in my future )
to be an excellent addition to a KNOPPIX system.

Yes K3b will work just fine -- although you can easily learn
the shell commands for cdrecord to blank and write to it
directly.

Two cautionary notes are in order:
1) packet writing is not yet here for KNOPPIX -- now you can only
blank a whole CDRW and the burn to the whole CDRW.
2) With a hard drive install it will take a little more work to get
the usb drive mounted. One way of course is to get the usb
CD working from the CD boot and then reinstall. To make
a hard drive install work without reinstalling you have to things
to /etc/fstab and I am not the one to ask about that.

My project for automatically saving and restoring /home/knoppix
to a CDRW is very preliminary -- but here is a link for what it's
worth.
http://www.knoppix.net/docs/index.php/BurnHome

Best Wishes,
paradocs

[Johnny3]

I'm having a similar problem with "writing" data to any USB device with Knoppix.

I'm being challenged on trying to move data from a HD to a USB drive pen. All the devices are recognized, but everything stops there...

The main error I keep getting is "Directory can not be created".

Can one of you "Guru's" take a moment a post some simple step-by-steps from booting with the Knoppix CD to configuring a USB device to copy and paste files?

Thanks!