Is there known problem with USB flash readers?

[Marten Vijn]

On Thu, 2010-06-24 at 11:47 +0100, Alex Markelov wrote:
> Hi Guys!
> 
> I have a strange problem with my flash card reader when dd'ing NanoBSD  
> images onto a CF card. It works for some time (3-4 writes of images),  
> then I start getting scsi error messages and dd hangs. I have to  
> disconnect/re-connect the reader to be able to write to CF again, but  
> sometimes even this trick doesn't work.
> 
> One day it stopped working for me and since I had a deadline to meet,  
> went to local shop and bought another one (different model and brand).  
> It worked fine for few write iterations and then it developed the same  
> problem. When I decided (out of desperation) to try the old one again,  
> it worked. So, I ended up using the two and swapping between it when  
> either of the units stopped working.
> 
> First thing I though that it might be the size of the image (2 or 4GB)  
> that I was writing with dd and it was heating up the electronics, but  
> yesterday a friend of mine stumbled upon the same problem and when his  
> flash reader (different brand and model to mine) stopped working, he  
> unplugged it from the FreeBSD box, plugged it in into his Linux laptop  
> and it worked without a problem. In his view it laid to rest my theory  
> about components heating too much as he did it without giving it a  
> minute of rest.
> 
> I vaguely recall there were problems with USB support in stable some  
> time ago, but I thought it was all fixed and searching the list and  
> the Internet doesn't give me anything.
> 
> Both of us were using 7-stable. I can email model of the card readers  
> later (not home at the moment).
> 
> Basically, I have two questions:
> 1) is it something that well known and not model related
> 2) is there a well known reliable model of card reader I can buy. I  
> don't mind the price if the device is rock solid.
> 
> Any pointers/ideas are greatly appreciated!

I have been using 8 (with new USB support) and haven't had issues with
for the last year. A possible workaround coud be using pxeboot and
install flashcard from unother device avoiding usb. (i use mfsbsd for
this). Maybe getting more info would to diagnose (dmesg, and maybe a
ktrace of the dd.  

2ct,
Marten



> Regards,
> Alex.
> 
-- 
Marten Vijn
linux 2.0.18 OpenBSD 3.6 FreeBSD 4.6
http://martenvijn.nl
http://opencommunitycamp.org
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