Re: [PLUG] Hot-swapping Linux RAID1 (was Re: Computer case)

[Rich Freeman <r-plug@thefreemanclan.net>]

>> Date: Mon, 13 Jun 2011 12:51:46 -0400
>> From: Julien Vehent<julien@linuxwall.info>
>
>>  I've never tried hot swapping sata drives used in a linux soft raid.
>>  Might be an interesting experience though:)
>

One other note: I'm not certain that the sata spec requires support
for hot swapping, or the specs on the standard ATX power supply for
that matter.  Even if linux supports it on the software end if the
hardware spec doesn't support it then you could get glitches when you
physically change the cables with the power on.

I know that higher-end server motherboards usually support
hot-swapping.  What I don't know is if desktop motherboards do.  For
this reason on low-end hardware RAID may not guarantee that there
isn't a failure when a drive fails - but it can greatly speed up the
recovery time to a working degraded system.

I would think that if nothing else true support for hot-swapping would
require that every drive have a dedicated power cable (no
daisy-chaining) and circuitry in the power supply to isolate drives.
I'm not sure what kinds of protection a low-end SATA drive has for
ensuring that hardware issues don't cause spikes/shorts/etc on the
line and I doubt that other drives on the same line will handle that
kind of stuff either.

Certainly interested if anybody knows otherwise...

RIch
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