From owner-freebsd-fs@freebsd.org  Wed Oct 19 11:26:25 2016
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To: Arrigo Marchiori <ardovm@yahoo.it>
cc: Arrigo Marchiori via freebsd-fs <freebsd-fs@freebsd.org>
Subject: Re: Random truncated files on USB hard disk with timeouts;
 how to debug?
In-reply-to: <20161019080005.GD93031@nuvolo>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
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Date: Wed, 19 Oct 2016 11:26:22 +0000
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--------
In message <20161019080005.GD93031@nuvolo>, Arrigo Marchiori writes:

>> If the drive has bad power supply, that may not happen.
>
>Yes, I understand. But, forgive me for insisting: there is an
>inconsistency that is _at filesystem level_ and _temporary_, and this
>really puzzles me.

Because the drive returns wrong data every so often and when
power is better returns correct data ?

End-to-End arguments in system design applies here:

Either you trust your drive, or you check everything it tells you
(ie: RAID with parity, ZFS or similar).

The only middle way is prayer.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.