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GNU GRUB is a boot loader package from the GNU Project. GRUB is the reference implementation of the Free Software Foundation's Multiboot Specification, which provides a user the choice to boot one of multiple operating systems installed on a computer or select a specific kernel configuration available on a particular operating system's partitions.
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The GUID Partition Table (GPT) is a standard for the layout of partition tables of a physical computer storage device, such as a hard disk drive or solid-state drive, using universally unique identifiers (UUIDs), which are also known as globally unique identifiers (GUIDs). Forming a part of the Unified Extensible Firmware Interface (UEFI) standard, it is nevertheless also used for some BIOSs, because of the limitations of master boot record (MBR) partition tables, which use 32 bits for logical block addressing (LBA) of traditional 512-byte disk sectors.
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Boot Camp Assistant is a multi boot utility included with Apple Inc.'s macOS that assists users in installing Microsoft Windows operating systems on Intel-based Macintosh computers. The utility guides users through non-destructive disk partitioning of their hard disk drive or solid-state drive and installation of Windows device drivers for the Apple hardware. The utility also installs a Windows Control Panel applet for selecting the default boot operating system.
TestDisk is a free and open-source data recovery utility that helps users recover lost partitions or repair corrupted filesystems. TestDisk can collect detailed information about a corrupted drive, which can then be sent to a technician for further analysis. TestDisk supports DOS, Microsoft Windows, Linux, FreeBSD, NetBSD, OpenBSD, SunOS, and MacOS. TestDisk handles non-partitioned and partitioned media. In particular, it recognizes the GUID Partition Table (GPT), Apple partition map, PC/Intel BIOS partition tables, Sun Solaris slice and Xbox fixed partitioning scheme. TestDisk uses a command line user interface. TestDisk can recover deleted files with 97% accuracy.
A volume boot record (VBR) is a type of boot sector introduced by the IBM Personal Computer. It may be found on a partitioned data storage device, such as a hard disk, or an unpartitioned device, such as a floppy disk, and contains machine code for bootstrapping programs stored in other parts of the device. On non-partitioned storage devices, it is the first sector of the device. On partitioned devices, it is the first sector of an individual partition on the device, with the first sector of the entire device being a Master Boot Record (MBR) containing the partition table.
The EFIsystem partition or ESP is a partition on a data storage device that is used by computers that have the Unified Extensible Firmware Interface (UEFI). When a computer is booted, UEFI firmware loads files stored on the ESP to start operating systems and various utilities.
In BSD-derived computer operating systems 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. Disklabels were introduced in the 4.3BSD-Tahoe release. Disklabels are usually edited using the disklabel utility. In later versions of FreeBSD, this was renamed as bsdlabel.
The partition type in a partition's entry in the partition table inside a master boot record (MBR) is a byte value intended to specify the file system the partition contains or to flag special access methods used to access these partitions.
In computing, a rigid disk block (RDB) is the block on a hard disk where the Amiga series of computers store the disk's partition and filesystem information. The IBM's PC equivalent of the Amiga's RDB is the master boot record (MBR).
The BIOS boot partition is a partition on a data storage device that GNU GRUB uses on legacy BIOS-based personal computers in order to boot an operating system, when the actual boot device contains a GUID Partition Table (GPT). Such a layout is sometimes referred to as BIOS/GPT boot.
A master boot record (MBR) is a type of boot sector in the first block of partitioned computer mass storage devices like fixed disks or removable drives intended for use with IBM PC-compatible systems and beyond. The concept of MBRs was publicly introduced in 1983 with PC DOS 2.0.
References
- 1 2 3 "Technical Note TN2166 – Secrets of the GPT". Apple. Retrieved 2013-02-24.
...a standard block size of 512 bytes...Apple did consider extending APM to support larger disks. However, as such a change would break all existing partitioning tools...
- ↑ Mac OS: Technical overview of disk volume structures
- ↑ Apple Support Communities: Guid Partition or Apple Partition? (2012)
- ↑ MacTech Magazine: Apple's Transition from Apple Partition Map to the GUID Partition Table by Criss Myers
- ↑ Apple Mailing List: Subject: Re: Apple Partition Scheme or GUID Partition Scheme Archived 2009-04-06 at the Wayback Machine , Timothy Standing, 2006-04-30
- ↑ Apple Support Communities: Create a bootable clone using Disk Utility (2014): an example of problems trying to boot on an Intel Mac using an APM partitioned drive.
- ↑ Apple Support Communities: Running Mavericks + FCPX on External Boot Drive? (2014): OS X Mavericks does not boot from APM partitioned drives.
- ↑ OWC: Booting your Intel Mac to an APM-formatted drive, M. Christopher Stevens
- ↑ Mac OS X 10.5: Creating and maintaining a bootable "universal" external disk
- ↑ Rebe, René; Klaus, Susanne (2007). "Creating custom Linux solutions – Apple Partition Map". T2 System Development Environment.
While the original intent was to handle various block sizes, in practice only 512 byte blocks are supported.
- ↑ "Yellow Dog Solutions – Attaching Firewire Disks to a Linux Box". Fixstars Corporation. Archived from the original on 2009-10-13. Retrieved 2013-02-24.
Comment: The command
pdisk -l /dev/sdashows a size of 63 blocks for theApple_partition_map. There is a multitude of examples like this to be found on the internet. - ↑ "IOApplePartitionScheme.h". Apple. 2009. Retrieved 2016-08-07.
