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 Mon,  8 Dec 2014 21:10:48 -0500 (EST)
Date: Mon, 8 Dec 2014 21:10:42 -0500
From: Brian N <fbsd@iozz.us>
To: Sean Chittenden <seanc@groupon.com>
Subject: Re: ZFS scrub on new disks gives cksum errors
Message-ID: <20141209021042.GA649@iozz.us>
References: <20141208155230.GA574@iozz.us> <5485CB35.5010608@multiplay.co.uk>
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On Mon, Dec 08, 2014 at 09:09:51AM -0800, Sean Chittenden wrote:
> I had this exact problem at home on my FreeNAS host when a box is plugged
> in to residential power that is "not clean."  If you plug this host in to a
> UPS it should clear things up instantly (find a sine wave UPS, not a
> digital stepping supply).  There's something about the fluctuating power or
> brownouts that ZFS is well suited to detecting (and became terrifying to me
> because wtf happened in the past pre-ZFS??).
> 
> -sc

Interesting.  I have a UPS (APC Back-UPS ES 550 (stepped)) on the same circuit
(residential power) that routinely gives me power outage messages where an
outage lasts 1-2 seconds.  Other electrical devices (lights, etc) are not
affected and I just thought that the UPS was very sensitive.  Thanks for the
reply.