External usb HDD disconnects, system gets messed up

[Marcin Wisnicki]

On Fri, 03 Dec 2010 10:06:58 +0100, Hans Petter Selasky wrote:

> On Friday 03 December 2010 02:37:43 Marcin Wisnicki wrote:
>> On Fri, 26 Nov 2010 08:17:47 +0100, Hans Petter Selasky wrote:
>> > I think that the USB part of your USB disk has died or there has been
>> > a firmware crash. Other OS'es will perform a complete device reset in
>> > this situation and sometimes that help, but still that is hiding a
>> > problem about the device. We don't do that on FreeBSD, and that might
>> > be the reason it does not recover.
>> 
>> Then print a warning. A lot of self-powered 2.5 disks I've used had the
>> same problem.
>> 
>> Also, would it be possible to somehow keep the kernel device if
>> physical device reappears within few seconds (with i/o temporarily
>> frozen) such that existing mount points keep working ?
> 
> Hi,
> 
> It would require some patching. It is not impossible to do, but I think
> that it should not be required. If a disk drive does not work properly
> with FreeBSD then you should be careful using it to store your data. It
> might be that the vendor of your USB HDD has only tested using one OS.
> It might be that OS is not FreeBSD.

I'm willing to bet that no vendor does testing with FreeBSD ;)

> 
> Please try to get support from your USB HDD manufacturer. I'm pretty
> sure that it is not a problem with FreeBSD USB or FreeBSD CAM layer.

Indeed, it happens in any OS. But Windows handles it gracefully, would be 
nice if FreeBSD did too.

> 
> I've been using a USB HDD enclosure for the last couple of years now
> without any problems at all, even though the USB connector is starting
> to get broken.
> 

Unfortunately it is impossible to know it before buying. Typical consumer 
does not use external hdd for more than couple of hours at a time so there 
are no reviews or complaints about it. You won't get your money returned 
either if it's just "sometimes a ding-dong sound is played if drive is 
used for more than 20 hours" which is all that happens in Windows.