An md/raid6 data corruption bug

Posted Aug 23, 2014 12:55 UTC (Sat) by Tomasu (guest, #39889)
In reply to: An md/raid6 data corruption bug by Wol
Parent article: An md/raid6 data corruption bug

I agree its safer to go with RAID6 in the long run, especially if you then mirror that ;)

My setup has two separate RAID5 arrays, in different machines. The NAS contains the main array, and my "home server" contains the backup array that has fewer, but larger disks also in a RAID5 which gets a rsync of the NAS array every night. It also stores other backups, so its not a direct clone, it just has a complete copy of the contents of the NAS.

It was all build ad-hoc as I had money, and there were sales on 2TB (nas) and 3TB (backup) disks.

I may test out raid6 again eventually when I need to upgrade the nas. but it'll be a while. I built my nas to handle 5 additional years of media and other downloads, WITHOUT deleting anything. But I sometimes delete stuff I really don't need to keep, which extends the lifetime by quite a bit. So it may be a while.

I do however have a VM storage box to finish building, and I may go raid6 for the vm storage. Not sure yet. The actual host of the array(s) will not likely be directly connected to the actual VM host, so it won't need to have more than like 90MBps throughput, and a decent sized raid6 outstrips that several times over (though a raid5 of the same number of spindles is about twice as fast, if not more).

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An md/raid6 data corruption bug

Posted Aug 23, 2014 14:51 UTC (Sat) by Wol (subscriber, #4433) [Link] (1 responses)

Quick maths ... 7 spindles, 2TB disks, raid 5. I make that 12TB storage.

6 spindles, 3TB disks, raid 6. I make that 12TB storage :-)

If disks are cheap you could upgrade the disks in the nas, then convert to raid 6 :-)

Dunno if you want to do that, though, I've just bought two 3TB disks, so I make the cost of your upgrade about £300 (Seagate Barracuda disks).

Cheers,
Wol

An md/raid6 data corruption bug

Posted Aug 23, 2014 15:06 UTC (Sat) by Tomasu (guest, #39889) [Link]

Indeed. But the actual storage is about 11TB. Doing a full convert would be a pain in the butt. :D It helps that I have the backup array though. So I could. I don't currently have enough 3TB disks to do that however. the backup array has 5 3TB disks. so it wouldn't actually be too expensive to do, just one more (or two, cause why not?) disk(s). If I do, I'll be waiting for a big sale on the 3TB disks. It's just not a huge priority for me at the moment. I have more than enough storage and enough protection at the moment to last quite a long time.