When 7 possible NAS products have available SAS support (FS,SA,UC ..7 NASes)
and all of them have 12 and more disks capacity
and 3 SAS capacity sizes are available (8,12,16TB)
and all of the NASes have been tested with min 12 disk RAID5 setup
and there was min one tested machine with same disk setup
Then:
3x12x7 = 252 disks in test
200 000 hours / 252 disk in test = 794 hours per disk = one month of test per single disk
But I hope, that Syno HW test scenario has been heavier. Then question how many real days have been the disks tested?
