Re: Filesystem corruption on RAID1

[Gionatan Danti <g.danti@assyoma.it>]

Il 17-08-2017 19:33 Wols Lists ha scritto:
> Which is fine until the drive, bluntly put, lies to you. Cheaper drives
> are prone to this, in order to look good in benchmarks. Especially as
> it's hard to detect until you get screwed over by exactly this sort of
> thing.

It's more complex, actually. The hardware did not "lie" to me, as it 
correcly flushes caches when instructed to do.
The problem is that a micro-powerloss wiped the cache *before* the drive 
had a chance to flush it, and the operating system did not detect this 
condition.

 From what I read on the linux-scsi and linux-ide lists, the host OS can 
not tell between a SATA link glitch and a SATA poweroff/poweron. This 
sound to me as a SATA specification problem, rather than a disk/OS one. 
However, a fix should be possible by examining some specific SMART 
values, which identify the powerloss/poweron condition.

Regards.

-- 
Danti Gionatan
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