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From: David Brown <david@westcontrol.com>
To: linux-raid@vger.kernel.org
Subject: Re: from 2x RAID1 to 1x RAID6 ?
Date: Thu, 09 Jun 2011 15:42:22 +0200	[thread overview]
Message-ID: <isqil8$1e7$1@dough.gmane.org> (raw)
In-Reply-To: <4DF0C81E.4020903@oldum.net>

On 09/06/2011 15:18, Nikolay Kichukov wrote:
> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
>
>
>
> On 06/08/2011 01:33 PM, David Brown wrote:
>
>> So you install your RAID10 (or RAID6, if you prefer) system, and
>> make sure you keep backups.  And if you /do/ get hit by a double
>> disk failure in the wrong place, you spend the day restoring
>> everything from the backups.  When management complain that a 24
>> hour downtime doesn't fit with their 99.99% uptime expectations,
>> you remind them that this is amortized over the next 27 years...
>
> Hi David,
>
> nice one ;-) Did you actually calculate 24 hours for those 99.99%
> within 27 years? ;-)
>

27.4 years is 10,000 days - so you can have 99.99% uptime with a 24-hour 
failure if you run for the rest of the 27.4 years without a hitch.  Of 
course, by the same logic you can claim 6 nine's uptime with a week's 
failure - as long as there are no more problems for the next 20,000 years...

:-)


> Cheers, - -Nik


  reply	other threads:[~2011-06-09 13:42 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-07 18:12 from 2x RAID1 to 1x RAID6 ? Stefan G. Weichinger
2011-06-07 20:07 ` Maurice Hilarius
2011-06-07 23:59   ` Thomas Harold
2011-06-08  8:06     ` Stefan G. Weichinger
2011-06-08  9:38     ` David Brown
2011-06-08 10:11       ` John Robinson
2011-06-08 10:33         ` David Brown
2011-06-08 14:20           ` Phil Turmel
2011-06-08 14:42             ` Stefan G. Weichinger
2011-06-09 13:18           ` Nikolay Kichukov
2011-06-09 13:42             ` David Brown [this message]
2011-06-08  1:16 ` John Robinson
2011-06-08  8:16   ` Stefan G. Weichinger
2011-06-08  9:43 ` David Brown
2011-06-08 12:31   ` Stefan G. Weichinger

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