Yes, but isn’t that just mean to setup the RAID5 to use 2 spear disk instead of 1 ?
This doesn’t require a more advanced raid controller, or more CPU power…
I really like the drobo philosophy, but the drobo FS is … expensive.
Ps.: I’m still interested in doing a real tech spec comparison.
Right now, I just need to have a network mirror raid to have my data safe, and access them under 2 computer (Win+Linux).
I feel like drobo doesn’t have this kind of product, and paying 700$ for a 2 disk raid seems overkill.
No, Dual-Disk Redundancy is NOT equivalent to RAID5 with 1, 2, or any number of hot spare(s).
In RAID5, when you lose one disk, it has to rebuild (onto a hot spare, or a replacement) during the rebuild, data is NOT protected against an additional drive failure. Lose another drive before rebuild is complete and you lose the array.
DDR equates in RAID-world to RAID6.
When the first drive fails, the array is still protected against an additional drive failure - even if rebuild has not yet completed.
When the second drive fails, then the array is no longer protected.
If a third drive fails before rebuild is complete, that’s when you lose the array.
So SDR, lose one drive OK, lose a second drive - data is gone.
In DDR, lose one drive OK, lose another drive OK, lose a third drive - data is gone.