The hardware: drive controllers


Availability of documentation depends on bus

drive controller    90% documented          98% working
IDE/PATA/SATA        80%           95%
SCSI/SAS                    90%           98%
RAID basics                  90%           95%
RAID management       10%            50%

Notes:
Promise, Highpoint refuse docs and provide binary drivers
Broadcom, NVIDIA, Marvell do not provide docs for their SATA
Adaptec SCSI & QLogic SCSI were forced open by our activism
Most RAID vendors provide only minimum docs
RAID management is almost completely undocumented

Dell/AMI/LSI RAID & VIA/AMD/Intel SATA/PATA being open sets
the standard for others to meet