Hi,

I try to connect a USB mass storage device (a hard drive mp3 player, archos jukebox recorder) but it doesn't work. It saies special device /dev/sda doesn't exist (it's a translation from french).

I can mount manually or automatically USB device like a USB key and camera but not the hard drive mp3 player. Why? Is not the same thing?
I use mandrake 10.1 so it's not old and the mp3 player is older so? Driver problem?

I entered in a prompt mount -t vfat /dev/sda /mnt/removable and for my USB key it works. I try the same with the hard drive and it doesn't work. the mp3 player saies that it is connected but the PC doesn't seem to see it.

Any Idea?
How can I see if there's a device connected or force it?

An other thing : I mount a same device like a USB 2 times because I entered it a second time without umount it. Then I try to umount it, but I had an error message like you can't umount, the device is working or the device has been mounted several times. It happened something similar with CD-Rom.

So How can I force umount or ... ?

Xavier

First of all, I'd advise you to check the the output from 'dmesg', since it looks as if you're runing udev, i.e the devices are created on the fly, and as needed. So there's no node /dev/sda when you remove a device that gets mapped to that device (a thumbdrive, for instance). So what do you see immediately after connecting the drive at the end of the output?

You can get information about devices mounted by udev with the "udevinfo" command.

So i use dmesd with the USB key and the USB hard drive. The USB hard drive is detected but there's a problem to settle it. The node sda isn't created like for USB key.

The message with the USB hard drive :
usb 1-1: new full speed USB device using uhci_hcd and address 4
scsi2 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 4
usb-storage: waiting for device to settle before scanning
usb 1-1: reset full speed USB device using uhci_hcd and address 4
scsi: Device offlined - not ready after error recovery: host 2 channel 0 id 0 lun 0
usb-storage: device scan complete


For the USB key :
usb 1-1: new full speed USB device using uhci_hcd and address 5
scsi3 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 5
usb-storage: waiting for device to settle before scanning
Vendor: Model: USB DISK 2.0 Rev: PMAP
Type: Direct-Access ANSI SCSI revision: 00
SCSI device sda: 243712 512-byte hdwr sectors (125 MB)
sda: Write Protect is off
sda: Mode Sense: 03 00 00 00
sda: assuming drive cache: write through
SCSI device sda: 243712 512-byte hdwr sectors (125 MB)
sda: Write Protect is off
sda: Mode Sense: 03 00 00 00
sda: assuming drive cache: write through
/dev/scsi/host3/bus0/target0/lun0: p1
Attached scsi removable disk sda at scsi3, channel 0, id 0, lun 0
Attached scsi generic sg0 at scsi3, channel 0, id 0, lun 0, type 0
usb-storage: device scan complete
end_request: I/O error, dev fd0, sector 0
end_request: I/O error, dev fd0, sector 0
usb 1-1: USB disconnect, address 5


So What can I do? I don't have any idea.
Driver?

Windows calls this device archos and in properties HITACHI also. Ii uses microsoft windows. Linux should have the same?

The output of the USB disk suggests ti may be being detected as sdb1, try mounting it with that. This based on:

host 2 channel 0 id 0 lun 0

maybe it is this, I will try. But I am wondering questions.

When I plug the key in the same USB entry, linux uses sda so why if I connect another peripheric in the same place, the name would change?
I check in the directory /sys/block. When I plug in the USB key it appears /sys/block/sda. When I plug in the USB hard drive, nothing. Why?

It is like something is detected but nothing next, no information. So it may me thing, it is a driver problem but it is not a recent device so the driver should already exist.

There is no information about the device in the database, taht's why Linux doesn't know how to treat this device like.

I tried to mount the USB device with sdb1 but it doesn't work :

Special device /dev/sdb1 doesn't exist

I am open to any idea to check I don't know? What is this database? Where can I check it? How can change this?

I'm using vmware 5.00 running linux FC6. Similar problem here. It seems like kernel can detect the usb mass storage and initialize scsi subsystem properly, but udev doesn't create node under /dev to the scsi disk.

here is the dmeg of the usb & scsi information:

usb 1-1: new full speed USB device using uhci_hcd and address 3
usb 1-1: configuration #1 chosen from 1 choice
SCSI subsystem initialized
Initializing USB Mass Storage driver...
scsi0 : SCSI emulation for USB Mass Storage devices
usbcore: registered new driver usb-storage
USB Mass Storage support registered.
usb-storage: device found at 3
usb-storage: waiting for device to settle before scanning
usb 1-1: reset full speed USB device using uhci_hcd and address 3
usb 1-1: reset full speed USB device using uhci_hcd and address 3
usb 1-1: reset full speed USB device using uhci_hcd and address 3
usb 1-1: reset full speed USB device using uhci_hcd and address 3
usb-storage: device scan complete

So any help?

Are you able to mount the device from the command line?

To find out the device name of the "drive" you may want to see:

As being an SCSI interface, the assignation of the logic units are in sda, sdb, etc.

What are the permissions of the device?

/dev/bus/usb/###/###

I just chmod'ed my Creative device to 7777 when gnomad2 barfed, and now it works fine.