BIOS Boot Partition (GPT)
From Wikipedia, the free encyclopedia
The BIOS Boot Partition is a partition on a data storage device that may be used by standard BIOS-based machines in order to boot when the partition table of the device is a GPT label.
The Globally Unique Identifier for the BIOS Boot Partition in the GPT scheme is 21686148-6449-6E6F-744E-656564454649. In the context of GPT labels, it is the BIOS equivalent of the EFI System Partition (which is used by systems based on EFI rather than BIOS).
When used, it contains the second stage of the boot loader program (the first being the code that is put in MBR). Use of this partition is not the only way BIOS-based boot can be performed on GPT labels; however, because unlike with DOS partition labels, there is no 63-sector gap immediately after the MBR, it can be convenient to add it to allow embedding the bootloader in a standalone region, as a replacement for the aforementioned gap.
This partition ID is relatively new, and its use is not yet widespread among BIOS/GPT implementations. The following utilities are known to support it:
- GRUB 2 (latest CVS): when a BIOS Boot Partition is found during installation, GRUB will embed itself in it.
- GPT-MBR: A GPT-aware MBR.
- GNU Parted (latest GIT).
- gpt(8) partition editor in NetBSD (in -CURRENT).
