System partition and boot partition
Encyclopedia
In Microsoft Windows
, the system partition and boot partition refer to:
The system partition can be different from the boot partition, although they are often on the same partition (drive C:). Windows setup places the initial system partition based on motherboard
BIOS
settings. Bitlocker requires a separate, unencrypted system partition for booting
.
The master boot record
is located at physical sector 0, just before the partition table
, and is therefore not contained inside any of the logical partitions or volumes.
Despite of Microsoft
's idiosyncratic terminology, it is possible to mark the boot partition as active and boot into it, if the partition is a primary partition, and the required files such as NTLDR and boot.ini for Windows XP
or older Windows NT
platforms exist on it. In a dual-boot scenario the system partition could be formatted with a FAT16
file system and contain an MS DOS operating system and a Recovery Console
. The old DOS boot sector of this partition is saved in a file bootsect.dos (or similar), and used as entry in the NTLDR boot.ini file. The new boot sector of this partition looks for and starts NTLDR, while the image of the old DOS boot sector looks for and starts DOS. Note that DOS boot sectors look for different files depending on the original equipment manufacturer
such as IBM
for PC DOS or Microsoft
for MS DOS.
Generally, newer boot schemes support older schemes; this is the reason why Microsoft
operating systems are typically installed in chronological order (oldest OS first, newest OS last), and why attempts to "repair" critical sectors with tools designed for older operating systems can cause havoc for newer operating systems.
The new Windows Vista startup process
supports the same and additional features; its boot sector looks for the new boot manager instead of NTLDR. Old fixmbr tools installing an NTLDR boot sector would destroy the newer boot sector, and therefore newer Windows versions typically use a separate system partition. The recommended layout consists of a primary hidden recovery partition followed by the primary NTFS
system partition (marked as active for booting), and a separate boot partition (in Microsoft terminology), the latter could be either a primary partition or a logical disk in an extended partition mounted as drive
For example, in the standard Linux
directory layout (Filesystem Hierarchy Standard
), boot files (such as the kernel
, initrd
, and boot loader GRUB) are mounted at
); these may or may not be separate partitions, but they are mounted in the same hierarchy.
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, the system partition and boot partition refer to:
- The system partition is a disk partition that contains the boot sectorBoot sectorA boot sector or boot block is a region of a hard disk, floppy disk, optical disc, or other data storage device that contains machine code to be loaded into random-access memory by a computer system's built-in firmware...
and files such as NTLDRNTLDRNTLDR is the boot loader for all releases of Windows NT operating system up to and including Windows XP and Windows Server 2003. NTLDR is typically run from the primary hard disk drive, but it can also run from portable storage devices such as a CD-ROM, USB flash drive, or floppy disk...
that are needed for bootingBootingIn computing, booting is a process that begins when a user turns on a computer system and prepares the computer to perform its normal operations. On modern computers, this typically involves loading and starting an operating system. The boot sequence is the initial set of operations that the...
Windows XPWindows XPWindows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
and earlier. (Windows VistaWindows VistaWindows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...
and Windows Server 2008 use a newer boot loader called bootmgr that replaces NTLDRNTLDRNTLDR is the boot loader for all releases of Windows NT operating system up to and including Windows XP and Windows Server 2003. NTLDR is typically run from the primary hard disk drive, but it can also run from portable storage devices such as a CD-ROM, USB flash drive, or floppy disk...
and is configured using BCDEdit.exe).
- The boot partition is the disk partition that contains the Windows operating systemOperating systemAn operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
files and its support files, but not any files responsible for bootingBootingIn computing, booting is a process that begins when a user turns on a computer system and prepares the computer to perform its normal operations. On modern computers, this typically involves loading and starting an operating system. The boot sequence is the initial set of operations that the...
.
The system partition can be different from the boot partition, although they are often on the same partition (drive C:). Windows setup places the initial system partition based on motherboard
Motherboard
In personal computers, a motherboard is the central printed circuit board in many modern computers and holds many of the crucial components of the system, providing connectors for other peripherals. The motherboard is sometimes alternatively known as the mainboard, system board, or, on Apple...
BIOS
BIOS
In IBM PC compatible computers, the basic input/output system , also known as the System BIOS or ROM BIOS , is a de facto standard defining a firmware interface....
settings. Bitlocker requires a separate, unencrypted system partition for booting
Booting
In computing, booting is a process that begins when a user turns on a computer system and prepares the computer to perform its normal operations. On modern computers, this typically involves loading and starting an operating system. The boot sequence is the initial set of operations that the...
.
The master boot record
Master boot record
A master boot record is a type of boot sector popularized by the IBM Personal Computer. It consists of a sequence of 512 bytes located at the first sector of a data storage device such as a hard disk...
is located at physical sector 0, just before the partition table
Partition table
The term partition table is most commonly associated with partition table but it may be used generically to refer to other "formats" that divide a disk drive into partitions, such as: GUID Partition Table, Apple partition map, or BSD disklabel.An alternative term to generically refer to partition...
, and is therefore not contained inside any of the logical partitions or volumes.
Despite of Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
's idiosyncratic terminology, it is possible to mark the boot partition as active and boot into it, if the partition is a primary partition, and the required files such as NTLDR and boot.ini for Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
or older Windows NT
Windows NT
Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
platforms exist on it. In a dual-boot scenario the system partition could be formatted with a FAT16
File Allocation Table
File Allocation Table is a computer file system architecture now widely used on many computer systems and most memory cards, such as those used with digital cameras. FAT file systems are commonly found on floppy disks, flash memory cards, digital cameras, and many other portable devices because of...
file system and contain an MS DOS operating system and a Recovery Console
Recovery Console
The Recovery Console is a feature of the Windows 2000, Windows XP and Windows Server 2003 operating systems. It provides the means for administrators to perform a limited range of tasks using a command line interface. Its primary function is to enable administrators to recover from situations...
. The old DOS boot sector of this partition is saved in a file bootsect.dos (or similar), and used as entry in the NTLDR boot.ini file. The new boot sector of this partition looks for and starts NTLDR, while the image of the old DOS boot sector looks for and starts DOS. Note that DOS boot sectors look for different files depending on the original equipment manufacturer
Original Equipment Manufacturer
An original equipment manufacturer, or OEM, manufactures products or components that are purchased by a company and retailed under that purchasing company's brand name. OEM refers to the company that originally manufactured the product. When referring to automotive parts, OEM designates a...
such as IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
for PC DOS or Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
for MS DOS.
Generally, newer boot schemes support older schemes; this is the reason why Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
operating systems are typically installed in chronological order (oldest OS first, newest OS last), and why attempts to "repair" critical sectors with tools designed for older operating systems can cause havoc for newer operating systems.
The new Windows Vista startup process
Windows Vista Startup Process
The startup process of Windows Vista, Windows Server 2008, Windows 7 and Windows Server 2008 R2 is different from any previous versions of Windows. For Windows Vista, the boot sector loads the Windows Boot Manager , which first looks for an active partition, then accesses the Boot Configuration...
supports the same and additional features; its boot sector looks for the new boot manager instead of NTLDR. Old fixmbr tools installing an NTLDR boot sector would destroy the newer boot sector, and therefore newer Windows versions typically use a separate system partition. The recommended layout consists of a primary hidden recovery partition followed by the primary NTFS
NTFS
NTFS is the standard file system of Windows NT, including its later versions Windows 2000, Windows XP, Windows Server 2003, Windows Server 2008, Windows Vista, and Windows 7....
system partition (marked as active for booting), and a separate boot partition (in Microsoft terminology), the latter could be either a primary partition or a logical disk in an extended partition mounted as drive
C:. More convoluted layouts with an OEM partition, or simpler layouts with system = boot partition, are possible.Other operating systems
It is interesting to note that in operating systems other than Windows and DOS the definitions of boot partition and system partition are just the opposite: the boot partition contains the boot files and the system partitions hold the operating system files.For example, in the standard Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
directory layout (Filesystem Hierarchy Standard
Filesystem Hierarchy Standard
The Filesystem Hierarchy Standard defines the main directories and their contents in Linux operating systems. For the most part, it is a formalization and extension of the traditional BSD filesystem hierarchy....
), boot files (such as the kernel
Kernel
-Computer science:* Kernel , the central component of most operating systems** The Linux kernel, from GNU/Linux operating systems** The Windows 9x kernel, used in Windows 95, 98 and ME...
, initrd
Initrd
In computing, initrd is a scheme for loading a temporary file system into memory in the boot process of the Linux kernel. initrd and initramfs refer to slightly different methods of achieving this...
, and boot loader GRUB) are mounted at
/boot/ while operating system files are mounted at / (the root directoryRoot directory
In computer file systems, the root directory is the first or top-most directory in a hierarchy. It can be likened to the root of a tree — the starting point where all branches originate.-Metaphor:...
); these may or may not be separate partitions, but they are mounted in the same hierarchy.
See also
- Windows NT Startup ProcessWindows NT Startup ProcessThe Windows NT startup process is the process by which Windows NT 4.0, Windows 2000, Windows XP and Windows Server 2003 operating systems initialize...
- Windows Vista Startup ProcessWindows Vista Startup ProcessThe startup process of Windows Vista, Windows Server 2008, Windows 7 and Windows Server 2008 R2 is different from any previous versions of Windows. For Windows Vista, the boot sector loads the Windows Boot Manager , which first looks for an active partition, then accesses the Boot Configuration...
- EFI System PartitionEFI System PartitionThe EFI System partition is a partition on a data storage device that is used by machines that adhere to the Extensible Firmware Interface. It contains the boot loader programs for all operating systems installed on the device, device driver files for other devices, and system utility programs...
- Windows To GoWindows To GoWindows To Go is a feature in Windows 8 that allows the entire system to run from USB mass storage devices such as flash drives and external hard drives....