March 2008 - WLUG - wlug.mailman3.com

Re: [Wlug] Missing /dev files

by Jamie Guinan

On Mon, 31 Mar 2008, vze284qe(a)verizon.net wrote: > On Sun, 30 Mar 2008 21:25:28 -0400 > Mike Frysinger <vapier(a)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? A few thoughts... Is the external USB drive self-powered? Did you power-cycle it at any point? The device itself might have gotten wedged. It might have shown up as /dev/sda* on some of those interim reboots, depending on whether there were any other usb storage devices present. "lsusb", and the tail command Eric suggested, are your friends. What is sda currently? [ these work on 2.6.23, not sure about earlier kernels ] $ cat /sys/block/sda/device/model $ cat /sys/block/sdb/device/model Anyway, glad to hear it at least works again. -Jamie

March 31, 2008

Re: [Wlug] Missing /dev files

by vze284qe＠verizon.net

On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier(a)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

March 31, 2008

Re: [Wlug] Missing /dev files

by Tim Keller

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(a)verizon.net> wrote: > On Sun, 30 Mar 2008 21:25:28 -0400 > Mike Frysinger <vapier(a)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(a)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".

March 31, 2008

Re: [Wlug] Missing /dev files

by Eric Martin

On Mon, Mar 31, 2008 at 12:40 AM, Karl Hiramoto <karl(a)hiramoto.org> wrote: > Chuck Noyes wrote: > > On Sun, 30 Mar 2008 21:25:28 -0400 > > Mike Frysinger <vapier(a)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

March 31, 2008

Re: [Wlug] Missing /dev files

by Karl Hiramoto

Chuck Noyes wrote: > On Sun, 30 Mar 2008 21:25:28 -0400 > Mike Frysinger <vapier(a)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/

March 31, 2008

Re: [Wlug] Missing /dev files

by Chuck Noyes

On Sun, 30 Mar 2008 21:25:28 -0400 Mike Frysinger <vapier(a)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

March 31, 2008

Re: [Wlug] Missing /dev files

by Mike Frysinger

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

March 31, 2008

Missing /dev files

by Chuck Noyes

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

March 31, 2008

installfest at WPI tomorrow (Fri, March 20)

by Mike Frysinger

maybe i missed it, but i dont think this was posted to the WLUG list: http://www.acm.wpi.edu/events/lif08/ -mike

March 20, 2008

Re: [Wlug] REMINDER: Meeting TONIGHT 7:00 PM

by Frank Sweetser

Richard Klein wrote: >> -----Original Message----- >> From: Chuck Anderson >> >> Last night we ate at Tech Pizza. Last month we ate at The >> Goat's Head restaurant at WPI. > > Was there any particular reason for going to The Goat's Head? Beer. > How was it? Pretty decent, IMO. > What distro do they use for the POS? WinCE. -- Frank Sweetser fs at wpi.edu | For every problem, there is a solution that WPI Senior Network Engineer | is simple, elegant, and wrong. - HL Mencken GPG fingerprint = 6174 1257 129E 0D21 D8D4 E8A3 8E39 29E3 E2E8 8CEC

March 20, 2008