Settings for maximum space with redundancy for the volume named primary.
Note: By default, RaidZ2 (mirrored RaidZ) is selected for a four disk configuration. Remember to select RaidZ1.
Theoretically, for four disks, one disk is lost for parity. Available capacity will be 75% (three out of four disks). FreeNAS estimates the available capacity as 68.2% (16.37/24). Actual capacity was slightly less at 63.73% (15.3/24).