[CentOS] RAID 6 - opinions

Thu Apr 11 18:34:03 UTC 2013
Digimer <lists at alteeve.ca>

On 04/11/2013 11:36 AM, m.roth at 5-cent.us wrote:
> I'm setting up this huge RAID 6 box. I've always thought of hot spares,
> but I'm reading things that are comparing RAID 5 with a hot spare to RAID
> 6, implying that the latter doesn't need one. I *certainly* have enough
> drives to spare in this RAID box: 42 of 'em, so two questions: should I
> assign one or more hot spares, and, if so, how many?
>
>         mark

I was building a home NAS over the holidays and had the same question 
(well, not hot spare, but 5 vs. 6). A good friend on mine pointed me to 
the following article;

http://www.zdnet.com/blog/storage/why-raid-5-stops-working-in-2009/162

I was using 6x 3 TB drives, so I decided to opt for RAID 6. About a 
month ago, a drive cacked out and I was *very* relieved to know that I 
was covered until I replaced the disk and it finished rebuilding.

If you have 42 disks, I'd not even think twice and I would use RAID 
level 6. If fact, with such a large number, I'd almost be tempted to 
break it into two separate RAID level 6 arrays and use something like 
LVM to pool their space, just to hedge my bets.

-- 
Digimer
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