On Nov 25, 2009, at 4:43 PM, Daniel Carosone wrote:
[verify on real hardware and share results]
Agree 110%.
Good :)
Yanking disk controller and/or power cables is an
easy and obvious test.
The problem is that yanking a disk tests the failure
mode of yanking a disk.
Yes, but the point is that it's a cheap and easy test, so you might
as well do it -- just beware of what it does, and most importantly
does not, tell you. It's a valid scenario to test regardless, you
want to be sure that you can yank a disk to replace it, without a
bus hang or other hotplug problem on your hardware.
The next problem is that although a spec might say that hot-plugging
works, that doesn't mean the implementers support it. To wit, there are
well known SATA controllers that do not support hot plug. So what
good is the test if the hardware/firmware is known to not support it?
Speaking practically, do you evaluate your chipset and disks for hotplug
support before you buy?
Testing scenarios that involve things like
disk firmware behaviour in response to
bad reads is harder -
If you wish to test the failure modes you
are likely to see, then you need a more
sophisticated test rig that will emulate
a device and inject the sorts of faults
you expect.
This is one reason I like to keep faulty disks! :)
Me too. I still have a SATA drive that breaks POST for every mobo
I've come across. Wanna try hot plug with it? :-)
-- richard
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