I just got my 500 GB ReadyNAS Duo last week, it was shipped with a Seagate ST3500830SCE. The first thing I did was update RAIDiator to 4.1.3. I ran on 1 disk for a few days and copied about 100 GB of data to it and everything seemed fine. I added a brand new Seagate 500 GB disk in slot 2 (ST3500641AS-RK firmware 3.AAE). It appeared to sync fine, it took about 3 hours and eventually frontview told me the sync was successful and the disks were "fully redundant". I had green lights for both disks in RAIDar and Frontview.
After a couple days of no issues running with both disks, I wanted to confirm that disk 2 had the same data as disk 1. So, I shutdown the ReadyNAS Duo using frontview and chose the "scan volume on reboot" option. After it shutdown, I pulled both disks and inserted disk 2 alone in slot 1. I powered it up and after a few minutes the leds started blinking 3 fast and 3 slow (Bad contents on root partition of disks). I open up RAIDar and it also says "Corrupt root". I can't get to frontview. So disk 2 is unbootable even though I never got any error or warning indicating it was anything other than an exact duplicate of disk 1. There is nothing in the "summary" logs in frontview other than success messages, I downloaded the full logs, but haven't examined them in detail.
Then I powered down and pulled disk 2 from slot 1 and put disk 1 back in slot 1 and left slot 2 empty. Booted fine, all data seems fine. I updated RAIDiator to 4.1.4 before trying again. I reinserted disk 2 in slot 2 and let it resync. After 3 hours it said the sync was complete and successful. I tried again to boot off of disk 2 alone using the same procedure I described above. The only difference was when I shutdown I did not choose the "scan volume on reboot" option. It didn't make any difference, the end result was the same. It would not boot on disk 2 and reported that I had a "Corrupt root".
I understand disks go bad and some disks are doa, but what scares me is that I had no indication that anything was wrong with disk 2 until I tried to boot from it. After this, how can I ever be confident again that disk 2 is a usable copy of disk 1?
I have another brand new seagate 500gb disk that I am going to try again in slot 2 to see if that is bootable after synching. I don't currently have a 3.5" usb enclosure, but I am going to get one and run the seagate diagnostics tool to see if there is anything physically wrong with the disk.
Any other suggestions would be welcomed.