In BSD-derived computer operating systems (including NetBSD, OpenBSD, FreeBSD and DragonFly BSD) and in related operating systems such as SunOS, a disklabel is a record stored on a data storage device such as a hard disk that contains information about the location of the partitions on the disk.
This was not originally viewed as a problem because there were only a small number of disk drives supported by each driver, and Unix only ran on one vendor's hardware.
This also presented a problem for commercially licensed Unix vendors, as support engineers would have to recompile the kernel before installing upgrades on a customer's machine.
For the 4.3-Tahoe release, which supported a non-Digital Equipment Corporation platform, the CCI Power 6/32, Berkeley implemented a new partitioning scheme based on an on-disk data structure and the disklabel(8) command.
[3] However, this system only works when the computer firmware simply loads and executes the boot loader without attempting to determine whether it is valid.