Specifies a set of discs.
- The set number of the RAID disc, referenced by each account.
- The block size of the file system (usually 2048). Under BSD with FFS, set this to your file system's fragment size (most likely an 8th of the block size).
- The first directory in the RAID array.
- The second directory in the RAID array. If you do not wish to use the built-in RAID functionality, this field should be set to the same as Dir0. You should not use the built-in RAID if you have a hardware RAID solution or if you're using another type of software RAID (like md on Linux).
- The third directory in the RAID array. The same notes that apply to Dir2 also apply to Dir3.