On 2013/04/11 10:36 AM, Joseph Spenner wrote: > ________________________________ > From: John R Pierce <pie...@hogranch.com> > To: centos@centos.org > Sent: Thursday, April 11, 2013 1:24 PM > Subject: Re: [CentOS] RAID 6 - opinions > > > On 4/11/2013 12:30 PM, m.r...@5-cent.us wrote: >>> Ok, listening to all of this, I've also been in touch with a tech from the >>> vendor*, who had a couple of suggestions: first, two RAID sets with two >>> global hot spares. > > I would test how long a drive rebuild takes on a 20 disk RAID6. I > suspect, very long, like over 24 hours, assuming a fast controller and > sufficient channel bandwidth. > > ---- > > But isn't that one of the benefits of RAID6? (not much degraded/latency > effect during a rebuild, less impact on performance during rebuild, so longer > times are acceptable?) > > ______________________________________________________________________ > If life gives you lemons, keep them-- because hey.. free lemons. > "♥ Sticker" fixer: http://microflush.org/stuff/stickers/heartFix.html > _______________________________________________ > CentOS mailing list > CentOS@centos.org > http://lists.centos.org/mailman/listinfo/centos Besides performance, the longer your rebuild takes, the more vulnerable you are to additional disk failure taking out your array. We've lost arrays that way in the past, pre-RAID6, lost two disks within a 6-hour period, and there went the array since the rebuild wasn't complete. RAID6 means you can handle 2 disk failures, but the third one will drop your array, if I'm remembering correctly. And the larger the number of disks, the higher the chance that you'll have disk failures...
Thanks! Miranda _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
