Drive errors in raidz array

krad kraduk at
Sat Jan 23 13:45:27 UTC 2010

On 22 January 2010 21:31, Dan Naumov <dan.naumov at> wrote:

> >> I have a system with 24 drives in raidz2.
> Congrats, you answered your own question within the first sentance :)
> ANSWER: As per the ZFS documentation, don't do raidz/raidz2 vdev
> groups bigger than 9 vdevs per group or bad things (tm) will happen.
> Google will tell you more.
> - Sincerely,
> Dan Naumov
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he didnt actually say that you have inferred it. However you are correct
about the vdev size.

The best configuration would probably be x2 raidz2 vdevs of 12 drives or 3x
of 8.

You could also go for 3x raidz of 7 drives with 3 hot spares. It really
depends on what redundancy/capacity ratio you want.

Having said all this im not convinced the errors you are seeing are
definitely due to having 24 drives in a vdev. I would expect some write
performance issues and slow rebuild times but not device errors

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