On 09/24/2009 07:35 AM, Rainer Duffner wrote: > > Am 24.09.2009 um 07:43 schrieb Fajar Priyanto: > >> Hi all, >> Sorry for the OT. >> I've got an IBM N3300-A10 NAS. It runs Data Ontap 7.2.5.1. >> The problem is, from the docs it says that it only supports either >> RAID-DP or RAID4. >> What I want to achieve is Max Storage Capacity, so I change it from >> RAID-DP to RAID4, but with RAID4, the maximum disk in a RAID Group >> decrease from 14 to 7. In the end, either using RAID-DP or RAID4, the >> capacity is the same. >> >> Now, why RAID5 is not supported? I believe using RAID5, I can get more >> storage capacity, can't I? >> I also notice with some onboard RAID controller, they only support >> either RAID0, RAID1, or RAID1+0. No RAID5. >> >> What's wrong with RAID5, is there any technical limitation with RAID5? > > > > Well, it depends on the disk-size: > http://www.enterprisestorageforum.com/technology/features/article.php/3839636 This info is VERY relevant ... you will almost ALWAYS have a failure on rebuild with very large RAID 5 arrays. Since that is a fault in a second drive, that failure will cause the loss of all the data. I would not recommend RAID 5 right now ... it is not worth the risk. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 253 bytes Desc: OpenPGP digital signature URL: <http://lists.centos.org/pipermail/centos/attachments/20090930/4a27bb97/attachment-0004.sig>