Basic data partition

From Wikipedia, the free encyclopedia

Microsoft-defined GPT attribute flags for BDPs^[1]
Bit number	Meaning
60	The volume is read-only and may not be mounted read-write.
62	The volume is hidden.
63	The operating system may not automatically assign a drive letter to the volume.

In Microsoft operating systems, when using basic disk partitioned with GUID Partition Table (GPT) layout, a basic data partition (BDP) is any partition identified with Globally Unique Identifier (GUID) of EBD0A0A2-B9E5-4433-87C0-68B6B72699C7.^[2]

In the GPT scheme, BDPs are the only partition types which Windows XP 64-bit can mount and normally assign drive letters.^[3]

According to Microsoft, the basic data partition is the equivalent to partition types 0x06, 0x07, and 0x0B (FAT16, NTFS, FAT32) in the traditional MBR partition table.^[2] In practice it is equivalent to 0x01, 0x04, 0x0C, and 0x0E (various older FAT partitions) types as well.

A Basic Data Partition can be formatted with any filesystem format, although most commonly BDPs are formatted with the FAT32 or NTFS filesystem formats. To programatically determine which filesystem format a BDP contains, Microsoft specifies that one should inspect the BIOS Parameter Block that is contained in the BDP's Volume Boot Record.

When a Microsoft operating system converts a GPT-partitioned basic disk to a dynamic disk, all BDPs are combined and converted to a single Logical Disk Manager data partition identified with GUID AF9B60A0-1431-4F62-BC68-3311714A69AD. This is analogous to the conversion from partition types 0x01, 0x04, 0x06, 0x07, 0x0B, 0x0C, and 0x0E to partition type 0x42 on MBR partitioned disks.