Hello, I had mounted an external usb drive /dev/sdb2 onto /media/sdb2 and was coping several mega-bytes of files to it when I got some I/O errors. Then I noticed that all of my /dev/sdb* files were missing from /dev. When I do an ls -al /dev, all the files are there except the sdb files. How can I get these back? I'm running Ubuntu 'gutsy' 2.6.20-16-generic. Thanks, -- -Chuck
On Sunday 30 March 2008, Chuck Noyes wrote:
I had mounted an external usb drive /dev/sdb2 onto /media/sdb2 and was coping several mega-bytes of files to it when I got some I/O errors. Then I noticed that all of my /dev/sdb* files were missing from /dev.
When I do an ls -al /dev, all the files are there except the sdb files.
How can I get these back? I'm running Ubuntu 'gutsy' 2.6.20-16-generic.
the device nodes only exist as the kernel thinks the device exists. if you got I/O errors and then the device nodes disappeared, the kernel probably detached the device. so even if you made the device nodes by hand, it wouldnt matter as the kernel still wouldnt think the device was attached. review your `dmesg` and if need be, unplug/plug in the USB device. -mike
On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier@gentoo.org> wrote:
On Sunday 30 March 2008, Chuck Noyes wrote:
I had mounted an external usb drive /dev/sdb2 onto /media/sdb2 and was coping several mega-bytes of files to it when I got some I/O errors. Then I noticed that all of my /dev/sdb* files were missing from /dev.
When I do an ls -al /dev, all the files are there except the sdb files.
How can I get these back? I'm running Ubuntu 'gutsy' 2.6.20-16-generic.
the device nodes only exist as the kernel thinks the device exists. if you got I/O errors and then the device nodes disappeared, the kernel probably detached the device. so even if you made the device nodes by hand, it wouldnt matter as the kernel still wouldnt think the device was attached. review your `dmesg` and if need be, unplug/plug in the USB device. -mike
dmesg shows many entries like this: new high speed USB device using ehci_hcd and address 10 usb 5-3: device descriptor read/8, error -110 usb 5-3: device descriptor read/8, error -110 Googling this message doesn't seem to provide much help. I have unpluged the device and even rebooted the computer. However, after a reboot, the /dev/sdb* files are still missing. -- -Chuck
Chuck Noyes wrote:
On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier@gentoo.org> wrote:
On Sunday 30 March 2008, Chuck Noyes wrote:
I had mounted an external usb drive /dev/sdb2 onto /media/sdb2 and was coping several mega-bytes of files to it when I got some I/O errors. Then I noticed that all of my /dev/sdb* files were missing from /dev.
When I do an ls -al /dev, all the files are there except the sdb files.
How can I get these back? I'm running Ubuntu 'gutsy' 2.6.20-16-generic.
the device nodes only exist as the kernel thinks the device exists. if you got I/O errors and then the device nodes disappeared, the kernel probably detached the device. so even if you made the device nodes by hand, it wouldnt matter as the kernel still wouldnt think the device was attached. review your `dmesg` and if need be, unplug/plug in the USB device. -mike
dmesg shows many entries like this:
new high speed USB device using ehci_hcd and address 10 usb 5-3: device descriptor read/8, error -110 usb 5-3: device descriptor read/8, error -110
Googling this message doesn't seem to provide much help.
I have unpluged the device and even rebooted the computer. However, after a reboot, the /dev/sdb* files are still missing.
The device files should be created by udev automatically when you pluging the device, or boot the PC.. When you un/plug the device you should see some info in dmesg. Perhaps you have some kind of error occurring. you could try rmmod "ehci_hcd" to try using USB 1.1 instead of usb 2.0. You could also try plugging it into a different hub or usb port on the PC. -- -- Karl Hiramoto http://karl.hiramoto.org/
On Mon, Mar 31, 2008 at 12:40 AM, Karl Hiramoto <karl@hiramoto.org> wrote:
Chuck Noyes wrote:
On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier@gentoo.org> wrote:
dmesg shows many entries like this:
new high speed USB device using ehci_hcd and address 10 usb 5-3: device descriptor read/8, error -110 usb 5-3: device descriptor read/8, error -110
Googling this message doesn't seem to provide much help.
I have unpluged the device and even rebooted the computer. However, after a reboot, the /dev/sdb* files are still missing.
The device files should be created by udev automatically when you pluging the device, or boot the PC.. When you un/plug the device you should see some info in dmesg. Perhaps you have some kind of error occurring. you could try rmmod "ehci_hcd" to try using USB 1.1 instead of usb 2.0. You could also try plugging it into a different hub or usb port on the PC.
I'd run a tail -f on /var/log/messages (or wherever your kernel messages go) so you can see what's happening as you plug / unplug the device. In Gentoo, the default for syslog-ng is to have it default log to tty12 so you can just flip over there. -- HTH Eric
Is this device at the end of a USB hub??? I ask because I run into this issue when I plug my PSP into a usb hub connexted to my FC8 box. If I plug directly in I don't see this issue... Just an idea... Thanks, Tim. On 3/30/08, Chuck Noyes <vze284qe@verizon.net> wrote:
On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier@gentoo.org> wrote:
On Sunday 30 March 2008, Chuck Noyes wrote:
I had mounted an external usb drive /dev/sdb2 onto /media/sdb2 and was coping several mega-bytes of files to it when I got some I/O errors. Then I noticed that all of my /dev/sdb* files were missing from /dev.
When I do an ls -al /dev, all the files are there except the sdb files.
How can I get these back? I'm running Ubuntu 'gutsy' 2.6.20-16-generic.
the device nodes only exist as the kernel thinks the device exists. if you got I/O errors and then the device nodes disappeared, the kernel probably detached the device. so even if you made the device nodes by hand, it wouldnt matter as the kernel still wouldnt think the device was attached. review your `dmesg` and if need be, unplug/plug in the USB device. -mike
dmesg shows many entries like this:
new high speed USB device using ehci_hcd and address 10 usb 5-3: device descriptor read/8, error -110 usb 5-3: device descriptor read/8, error -110
Googling this message doesn't seem to provide much help.
I have unpluged the device and even rebooted the computer. However, after a reboot, the /dev/sdb* files are still missing.
-- -Chuck _______________________________________________ Wlug mailing list Wlug@mail.wlug.org http://mail.wlug.org/mailman/listinfo/wlug
-- I am leary of the allegiances of any politician who refers to their constituents as "consumers".
On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier@gentoo.org> wrote:
On Sunday 30 March 2008, Chuck Noyes wrote:
I had mounted an external usb drive /dev/sdb2 onto /media/sdb2 and was coping several mega-bytes of files to it when I got some I/O errors. Then I noticed that all of my /dev/sdb* files were missing from /dev.
When I do an ls -al /dev, all the files are there except the sdb files.
How can I get these back? I'm running Ubuntu 'gutsy' 2.6.20-16-generic.
the device nodes only exist as the kernel thinks the device exists. if you got I/O errors and then the device nodes disappeared, the kernel probably detached the device. so even if you made the device nodes by hand, it wouldnt matter as the kernel still wouldnt think the device was attached. review your `dmesg` and if need be, unplug/plug in the USB device. -mike
Well....this is really strange! I booted up another kernel a 2.6.18, and I noticed that the /dev/sdb* files were still missing! All of the other /dev files were there. So I shut down the computer - power off, unplug, remove battery (it's a laptop) and waited a minute. I reinstalled the battery, plugged it in and booted up the usual kernel, et voila...the /dev/sdb* files reappeared!! All looks good! Even Linux has some strangeness I guess. I don't know what caused this in the first place...transient lightning bolts? spurrious darktrons? Anyway, it's working. Thanks to all who offered help. -Chuck -- -Chuck
vze284qe@verizon.net wrote, on Mar 31, 2008 at 19:27 EDT:
So I shut down the computer - power off, unplug, remove battery (it's a laptop) and waited a minute. I reinstalled the battery, plugged it in and booted up the usual kernel, et voila...the /dev/sdb* files reappeared!! All looks good! Even Linux has some strangeness I guess.
I don't know what caused this in the first place...transient lightning bolts? spurrious darktrons?
I've got a flash card reader that, if it's got a card in it when the computer is turned on, will forever fail to recognise that it's got media. However, if I insert the media after Linux has recognised and reset the device, all is good. Perhaps you had a situation like that? I blame BIOS weirdness, really. -- Aaron Haviland 34 Wayne Ave, Dudley, MA
participants (8)
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Aaron Haviland -
Chuck Noyes -
Eric Martin -
Karl Hiramoto -
Mike Frysinger -
Stephen Daukas -
Tim Keller -
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