This is an article which discusses the increase in storage capacity while performance and hard error rates have not improved significantly in years, and what this means for protecting data in large storage systems.
"The concept of parity-based RAID (levels 3, 5 and 6) is now pretty old in technological terms, and the technology's limitations will become pretty clear in the not-too-distant future â" and are probably obvious to some users already. In my opinion, RAID-6 is a reliability Band Aid for RAID-5, and going from one parity drive to two is simply delaying the inevitable."
Member since:
2005-07-08
Adam Leventhal explains it much better than I can:
http://blogs.sun.com/ahl/entry/double_parity_raid_z
ZFS definitely helps, so does a good backup strategy. You are only as safe as your last successful restore.