From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gionatan Danti Subject: Re: Filesystem corruption on RAID1 Date: Thu, 17 Aug 2017 22:50:13 +0200 Message-ID: <83f4572f09e7fbab9d4e6de4a5257232@assyoma.it> References: <20170713214856.4a5c8778@natsu> <592f19bf608e9a959f9445f7f25c5dad@assyoma.it> <770b09d3-cff6-b6b2-0a51-5d11e8bac7e9@thelounge.net> <9eea45ddc0f80f4f4e238b5c2527a1fa@assyoma.it> <7ca98351facca6e3668d3271422e1376@assyoma.it> <5995D377.9080100@youngman.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5995D377.9080100@youngman.org.uk> Sender: linux-raid-owner@vger.kernel.org To: Wols Lists Cc: Roger Heflin , Reindl Harald , Roman Mamedov , Linux RAID List-Id: linux-raid.ids 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 Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti@assyoma.it - info@assyoma.it GPG public key ID: FF5F32A8