The Redundant Array of Independent Disks (RAID) technology has become the standard way of mirroring hard drives within a machine or combining multiple hard drives to form one giant partition. In many types of RAID arrays, if one disk fails, the system can continue to run without data loss until you replace the failed disk or a second disk fails.
You can get RAID from the hardware or have the operating system perform the RAID operations. Hardware RAID controllers seem nice, but are in reality just decent disk controllers that run special software. Using the
softraid(4) driver, OpenBSD can do the same thing, letting you build RAID arrays out of plain disks. You can do just about everything you can with a hardware RAID controller with ...