[sean13013]

Sorry, I should have worded that better. I know what the message means, but what do you make of the fact that it found & repaired corrupt data? If I understand right (and correct me if I'm wrong), corrupt data should only occur if some bit of hardware is failing or possibly after improper shutdown. Am I wrong? Is it no big deal to see scrubs repairing data?

[jspiros]

My understanding is that some significant (thousands of bytes) silent corruption is inevitable when you start reaching huge capacities over long-ish periods of time; even cosmic radiation has the potential to flip a few bits here and there every once in a while.

http://en.wikipedia.org/wiki/Data_corruption#Silent_data_cor...

So, yes, I think even with the best hardware, and proper maintenance, seeing some data repaired in a scrub is to be expected.

(That said, I did spend way too long using technology [SATA PM] that often failed and made it impossible for me to run a scrub. It's very possible that normal error rates are more like what I'm seeing now, a single byte every month or so, and that the megabyte figure is representative of errors from the days of my arrays dropping out unexpectedly.)