Disk array controller

While hardware RAID controllers have been available for a long time, they initially required expensive Parallel SCSI hard drives and aimed at the server and high-end computing market.

SCSI technology advantages include allowing up to 15 devices on one bus, independent data transfers, hot-swapping, much higher MTBF.

Around 1997, with the introduction of ATAPI-4 (and thus Ultra-DMA-Mode, which enabled fast data transfers with less CPU utilization) the first ATA RAID controllers were introduced as PCI expansion cards.

Unlike the network interface controllers for Ethernet, which can be usually be configured and serviced entirely through the common operating system paradigms like ifconfig in Unix, without a need for any third-party tools, each manufacturer of each RAID controller usually provides their own proprietary software tooling for each operating system that they deem to support, ensuring a vendor lock-in, and contributing to reliability issues.

[2] For example, in FreeBSD, in order to access the configuration of Adaptec RAID controllers, users are required to enable Linux compatibility layer, and use the Linux tooling from Adaptec,[3] potentially compromising the stability, reliability and security of their setup, especially when taking the long term view in mind.

[8] With bioctl, the feature set is intentionally kept to a minimum, so that each controller can be supported by the tool in the same way; the initial configuration of the controller is meant to be performed through card BIOS,[7] but after the initial configuration, all day-to-day monitoring and repair should be possible with unified and generic tools, which is what bioctl is set to accomplish.