dismas

Is there a formula to calculate NAS if LHD is NOT less than or equal to THD / DF?

Let's say I have a 3 TB pool consisting of a 1 TB drive and a 2 TB drive. If I enable 2x duplication on the entire pool, I assume I can only store 1 TB in the pool since even though there's 3 TB available, because everything on the 2 TB drive must have a copy on the remaining drive, and thus is limited is 1 TB. Is this understanding correct? What if I instead had a 3 TB pool consisting of 3x 1 TB drives - in this case, if I enable 2x duplication over the entire pool, is the usable space on the pool still limited to 1 TB? Or is DrivePool capable of spreading the files out across all 3 drives, leading to an effective storage capacity of 1.5 TB?