[CentOS] RAID 5 setup?

Thu Mar 25 22:18:21 UTC 2010
John R Pierce <pierce at hogranch.com>

Boris Epstein wrote:
> You surely do have a point there. However, it is still not all that
> likely that a disk will fail during the rebuild time in question (what
> are we talking? some hours max?)
>   

8 disks is about the upper limit I'd suggest for a single raid group on 
any sort of system.

rebuilding a 8x1.5TB raid5 could easily take a full day or more.... will 
you have an online hotspare?  if not, then the rebuild time includes how 
long it takes you to realize there's a bad drive, procure and install 
the replacement, /AND/ the umpteen hours for the rebuild.

personally, I prefer using raid10 or 1+0 (more or less the same thing), 
and for anything above a 2 disk mirror, I prefer to use a proper 
hardware raid controller... for 8+ disks, I'd likely be looking at 
external storage arrays such as the IBM DS3000 family.