Ready for expansion (RN Pro Pioneer Edition)-Seeking Advice

mdgm wrote:
Disk scrubbing does a resync to make sure the disks are still synced sector by sector, that the parity distributed amongst the disks is fixed if there is a problem with it. It's not going to reduce your error count, that will stay for that disk. However it will make sure the disks are in sync.....

Please tell me if I am understanding this correctly.

First ATA error, this is one explanation of what I found:

ATA error: The SATA controller on the ReadyNAS was unable to communicate with the hard drive.

Does this (ATA error) mean a portion of the disk could not be read? And scrubbing ensures all my data is intact across all my six disks, even if this involves "moving" data from the portion of the disk not readable to another location (NAS knows what this 'unreadable' data based on my dual-redundancy setup.