I just looked at my Drobo Dashboard and saw the following:
on my Drobo Pro I have 13.26 TB Used Space, 2.73 TB Free Space and 1.86 Unallocated Space = a Total of 17.86 TB.
What is the unallocated space?
I don’t find it on my 5D nor on my Drobo Mini.
Also would like to know, if the Drobo Pro with Firmware 1.2.2 would support 4 TB drives?
thanks for the other info,
if your drobo pro is using DDR (dual disk redundancy) then it is using 2 of the largest drive sizes of capacity for protection…
if this is the case then i think your drives of this:
3+3+3+3+3+3+3+2 = 23TB (physical capacity)
would used up 3+3tb, leaving you with this:
3+3+3+3+3+2 = 17TB (available capacity)
(on my drobos, i usually multiply this by 0.9 to get an estimated usable capacity, as the filesystem/formatting usually reduces this for actual TB, which would sound like you would have this actually usable: 15.3TB)
this seems around the 15.xTB that your current drobo is showing (used+free) and seems to make sense to me.
un-allocated might simply mean used for protection or wasted due to normal filesystem, but i dont have a drobo pro to verify that for you.
some other forum users have had experience with a drobo pro, so hang in there and hopefully someone else can reply back for you too