Why RAID 5 Stops Working In 2009

Lally Singh recommends a ZDNet piece predicting the imminent demise of RAID 5, noting that increasing storage and non-decreasing probability of disk failure will collide in a year or so. This reader adds, "Apparently, RAID 6 isn't far behind. I'll keep the ZFS plug short. Go ZFS. There, that was it." "Disk drive capacities double every 18-24 months. We have 1 TB drives now, and in 2009 we'll have 2 TB drives. With a 7-drive RAID 5 disk failure, you'll have 6 remaining 2 TB drives. As the RAID controller is busily reading through those 6 disks to reconstruct the data from the failed drive, it is almost certain it will see an [unrecoverable read error]. So the read fails ... The message 'we can't read this RAID volume' travels up the chain of command until an error message is presented on the screen. 12 TB of your carefully protected — you thought! — data is gone. Oh, you didn't back it up to tape? Bummer!"

Comments

RAID doesn't protect against your worst enemy

[YesIAmAScript]

rm -r *

Seriously, you're kidding yourself if you think RAID is protecting you.

Re:RAID doesn't protect against your worst enemy

[cbreaker]

Easily solved by file system snapshots.. which you should be doing for an important file server no matter what operating system you're using.

Re:RAID doesn't protect against your worst enemy

[EvilRyry]

Unfortunately very few file systems actually implement them in a form that's usable under heavy loads.

Re:Carefully protected?

[WhatAmIDoingHere]

A "Redundant Arrays of Inexpensive Disks" array?

I'd like to buy one of those, do you mind if I stop at the automated teller machine machine first? Let me just type in my personal identification number number...