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To: Simon Shapiro <Shimon@i-Connect.Net>
cc: "burt f." <burt@focusplus.com>, freebsd-hackers@FreeBSD.ORG
Subject: Re: ? power outages and file system corruption 
In-reply-to: Your message of "Mon, 25 Aug 1997 23:24:50 PDT."
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Date: Wed, 27 Aug 1997 11:31:07 -0500
From: Wm Brian McCane <root@bmccane.uit.net>
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> 
> Hi "burt f.";  On 26-Aug-97 you wrote: 
> >  
> >  
> >  Is the only way to protect against power-outage-caused file system
> >  corruption to install a UPS?  Someone mentioned to me that Sun
> >  (yeah, i know it's Solaris, but i just wanted to know if there was
> >  something analogous in FBSD) has some sort of disk/FS caching to
> >  protect against this.
> 
> In theory, a journaling filesystem will do that.  Veritas is a good name
> for these.  The problem with most of these is that a $300 UPS is cheaper
> and more reliable.  Most such filesystems are attached to such an increase
> in complexity that the most common cause of curruption is a filesystem code
> bug.  Even a UPS does not help you then.
> 
> Simon
> 
There is another benefit to buying a UPS.  At my last job we used to lose 
power all the time (5-10 ton electric cranes).  After I bought the UPS, the 
power outtages stopped.  When I became self-employed, I bought a new UPS for 
my home computer, I haven't lost electrical power here for almost 2 years 
now.  I feel this is empirical evidence that UPS' prevent power outtages 8->.

	brian