Re: cciss vs IDE (was: lvm with raid)
--On Friday, July 02, 2004 14:18 +1000 Russell Coker <firstname.lastname@example.org>
Physically plugging or unplugging a P-ATA (IDE) disk is not supported.
Some people have managed to get it to work, but it required the type of
engineering effort that most people won't want to apply to their
production machines (IE don't do it).
If you have a hot-spare disk in the machine then you can have it take the
place of a disk that dies while the machine is running and then replace
the defective hardware during a scheduled maintenance time.
Except that in my experience a dead IDE drive takes the whole system with
it even with MD RAID, the system just locks up. (yes even on say three
This isn't the case with decent hardware IDE RAID controllers (3ware comes
to mind, promise does NOT)
YMMV of course...I've kind of thought about doing another experiment here
lately I've got a handful of older drives at home that I've thought about
trying failure scenarios (c'mon, don't tell me you're not the least bit
interested in taking a ball peen hammer to a drive in a running system!!!)
The cheapest hot-swap disk array might be to have the disks in USB
devices, USB supports hot-swap. I haven't tried having more than one
USB block device in a system so I don't know how well this would work.
My USB 2.0 IDE disk box can sustain over 30MB/s so there's no great
performance loss unless you have one of the newest and fastest IDE disks.
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