Pete-

You may want to try this:

Create a script to echo the value that you need and save it to a file,
say:

/lib/udev/usbHubFix
chmod 755 /lib/udev/usbHubFix

Then, create a udev rule in /etc/udev/rules.d/81-usbHubFix
with the contents:

BUS=="usb", ACTION=="add", RUN+="usbHubFix"

Save, and restart udev.

HTH,

-Gadi

On Thu, 2007-08-16 at 07:14 -0400, Peter Billson wrote:
> Jim Kronebusch wrote:
> > On Wed, 15 Aug 2007 13:53:15 -0400 (EDT), Peter Billson wrote
> >> Hello *,
> >>    I have a problem with accessing USB drives through an un-powered USB 
> >> hub.
> >>
> >>   The problem is a well known issue due to changes in the 2.6 kernel so
> >> that USB works "right." The "fix" is simply to echo a value to the
> >> proper place under /sys/bus/usb/devices when the USB drive is plugged
> >> in.
> >>
> >>   I have a simple little shell script to do the job and it works fine if
> >> run manually.
> >>
> >>   My problem is I can not seem to get the script to execute automatically
> >> on the LTSP client when a USB device is plugged in. I am sure this is
> >> just my total lack of knowledge about udev and am hoping that someone
> >> can point me to how and where to add the correct udev rule so that this
> >> magic happens.
> > 
> > This is a very basic explanation from a person with very minimal knowledge 
> > on the topic.
> >  But from what I understand the usb device sends a signal when plugged in.  
> > So you plug
> > in your USB hub and no devices are plugged in when the signal is sent thus 
> > no drives are
> > mounted.  Now when you plug a drive into the hub a signal is sent, but it 
> > stops at the
> > hub and never makes it to the client, so no drive is mounted.  If you plug 
> > the drive
> > into the hub, then plug the hub into the client, there is a drive present 
> > when the
> > signal is sent so the drive is mounted.  I think Scott Balnaeves said that 
> > you could
> > possibly probe the usb device every so often to see if a drive was present, 
> > but I can't
> > exactly remember.  If you contact him I'm sure he'll shed a great amount of 
> > light on
> > what is happening.
> > 
> > Jim
> 
> Jim,
>    Thanks for the reply. I didn't get too much into the actual problem 
> since the problem itself isn't LTSP related.
> 
>    The actual "problem" is that the newer 2.6 kernels enforce the USB 
> power limits that are part of the USB specification. Older kernels did not.
> 
>    Soooo technically the older kernels (where the USB thumb drives 
> worked on unpowered hubs) where broken and the new kernels (where the 
> thumb drives don't work) are fixed.
> 
>     Much grumbling has ensued but the kernel guys are correct in their 
> implementation. After all if you just start ignoring standards and doing 
> what is convenient you would end up with M$ Vista!
> 
>    Anyway, in my case the thumb drive is seen when it is plugged into 
> the hub but the kernel chooses not to configure it based on how much 
> power it draws.
> 
>    Forcing the kernel to configure the device is trivial - my little 
> script does that - but my LTSP related problem is that I can not figure 
> out how to write a udev rule to run the script automatically on the client.
> 
>    I was hoping Scotty (the self-taught LTSP udev guru) was not too busy 
> and had some helpful advice but I am sure he is busy.
> 
> 
> Pete Billson
> --
> http://www.elbnet.com
> ELB Internet Service, Inc.
> Reliable Tech Support for New Jersey's Public Libraries
> 
> 
> > 
> 
> 
> -------------------------------------------------------------------------
> This SF.net email is sponsored by: Splunk Inc.
> Still grepping through log files to find problems?  Stop.
> Now Search log events and configuration files using AJAX and a browser.
> Download your FREE copy of Splunk now >>  http://get.splunk.com/
> _____________________________________________________________________
> Ltsp-discuss mailing list.   To un-subscribe, or change prefs, goto:
>       https://lists.sourceforge.net/lists/listinfo/ltsp-discuss
> For additional LTSP help,   try #ltsp channel on irc.freenode.net
-- 
--------------------------------------------------------
Gideon Romm | Proud LTSP Developer
[EMAIL PROTECTED]

Support LTSP!  Buy your hardware at:

        www.DisklessWorkstations.com
        www.DisklessThinClients.com 
 
(use coupon code: LTSP5P for 5% off thin clients from DisklessThinClients.com)


-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_____________________________________________________________________
Ltsp-discuss mailing list.   To un-subscribe, or change prefs, goto:
      https://lists.sourceforge.net/lists/listinfo/ltsp-discuss
For additional LTSP help,   try #ltsp channel on irc.freenode.net

Reply via email to