0 - Disk striping
1 - Disk mirroring
2 - Disk striping across disks, w/ error correction code (ECC) across disks
3 - Disk striping across disks, w/ parity information on single disk (3+ disks, not recommended for intensive apps)
4 - Disk striping in larger data blocks (level 3 is byte level), w/ parity information on single disk
5 - Disk striping with parity across multiple disks (3+ disks, total parity data equals size of one disk)
6 - Disk striping with two forms of parity across multiple disks (protects against dual disk failures)
Mirroring - duplicates data on one drive to another to allow identical drives (slower writing)
Duplexing - each drive has its own disk controller. just in case one fails (better performance but more expensive)
Striping - the spreading of data across multiple drives
Multiple RAID Levels:
01 (RAID 0 then RAID 1) - 2 sets of 5 disks. Each set is a RAID 0 array, mirror the sets. A so called "mirror of stripes"
Min disks: 4 (in which only 2 would be used for storage)
10 (RAID 1 then RAID 0) - 5 sets of 2 disks. Each set is a RAID 1 array, then stripe across sets. A so called "stripe of mirrors"
(Some info from PCGuide.com)
30 min disks: 6
50 min disks: 6
Hard drives should always be same manufacturer, size, and type for best performance.
Adaptec ATA RAID 1200A
RAID: 0 (2+), 1 (2+), 01 (4), JBOD (2+)
Rebuilding RAID1: Replace bad drive, delete RAID relationship, rebuild array (verify)