[OpenIndiana-discuss] General ZFS questions

[Michelle Knight]

I have a system with a Raidz running three 1.5tb drives on internal SATA.

Two 2tb drives are hooked up on esata in a removable drive bay; they are 
configured as a zfs mirror and I use these for irregular backup.

It seems that whenever I do a general scrub on a monthly basis on the internal 
set, there is always the odd two or three cksum errors floating around. Of 
course, ZFS corrects them. But is this usual? To get a few errors on hard 
drives? Should I expect it to be 0 all the time?

On the external drives, I've just copied a little over 1tb of data and I think 
I've had about 10 cksum errors after the copy.

Is this to be expected when using ZFS, or is this indicating something wrong 
with my system somewhere?

Thanks for any advice.