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

Re:Carefully protected?

[techess]

I always love it when Fed-Ex destroys something and then tries to hide it. One day I walked past the shipping office and I smelled the very strong odor of hydraulic oil coming from the room. I take a look inside since we shouldn't be receiving anything that has hydraulic oil in it. I found a bunch of boxes with the local Detroit Airport logo all over them and sealed with DET labeled tape. The cardboard was completely soaked through with the oil.

I carefully opened one of the boxes and found it contained servers! It appears that the original boxes got in some sort of accident at the airport and were completely soaked. At the airport Fed-Ex or the baggage handlers did us a "favor" and re-boxed everything. The servers were so coated (and filled) that even the new boxes were completely soaked through and the bottoms of the boxes were starting to pull apart. The Fe-Ex guy (so we wouldn't refuse them) dropped them off at lunch and then got some random person in the hall to sign off on it.

We had to pay for new servers to be built ASAP and shipped overnight (UPS this time) at huge cost for us. Since someone had signed off on the package we then had a very long fight to get Fed-Ex to pay for the equipment they destroyed. We never got the extra cost for the overnight shipping and the rush build reimbursed.