On Tue 2009-08-25 16:56:40, david@lang.hm wrote:

On Wed, 26 Aug 2009, Pavel Machek wrote:

quoted

There are storage devices that high highly undesirable properties
when they are disconnected or suffer power failures while writes are
in progress; such devices include flash devices and MD RAID 4/5/6
arrays.

change this to say 'degraded MD RAID 4/5/6 arrays'

also find out if DM RAID 4/5/6 arrays suffer the same problem (I strongly 
suspect that they do)

I changed it to say MD/DM.

then you need to add a note that if the array becomes degraded before a  
scrub cycle happens previously hidden damage (that would have been  
repaired by the scrub) can surface.

I'd prefer not to talk about scrubing and such details here. Better
leave warning here and point to MD documentation.

quoted

THESE devices have the property of potentially corrupting blocks being  
written at the time of the power failure,

this is true of all devices

Actually I don't think so. I believe SATA disks do not corrupt even
the sector they are writing to -- they just have big enough
capacitors. And yes I believe ext3 depends on that.
								Pavel
-- 
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