The Windows 2000 Boot Process
- Preboot and Boot Sequences
- Windows 2000 Load Phases
- Booting Windows 2000 Safe Mode
- Related Publications
The Windows 2000 boot process can differ, depending on its platform. This article discusses Windows 2000 preboot and boot sequences on Intel and RISC platforms.
Paul T. Ammann is the author of IP Solutions for Windows 2000 (Prentice Hall PTR, 2001, ISBN 0-13-091170-4).
The Windows 2000 boot process differs slightly between the Intel and RISC platforms. In this article, we look at the differences between these two platforms.
Preboot and Boot Sequences
On Intel-based systems, the boot process is made up of a preboot sequence and boot sequence. The preboot sequence consists of the following steps:
Power-On Self Tests (POST) are run.
The boot device is found, the Master Boot Record (MBR) is loaded into memory, and its program is run.
The active partition is located, and the boot sector is loaded.
The Windows 2000 loader (NTLDR) is then loaded.
The boot sequence executes the following steps:
The Windows 2000 loader switches the processor to the 32-bit flat memory model.
The Windows 2000 loader starts a mini-file system.
The Windows 2000 loader reads the BOOT.INI file and displays the operating system selections (boot loader menu).
The Windows 2000 loader loads the operating system selected by the user. If Windows 2000 is selected, NTLDR runs NTDETECT.COM. For other operating systems, NTLDR loads BOOTSECT.DOS and gives it control.
NTDETECT.COM scans the hardware installed in the computer, and reports the list to NTLDR for inclusion in the Registry under the HKEY_LOCAL_MACHINE_HARDWARE hive.
NTLDR then loads the NTOSKRNL.EXE, and gives it the hardware information collected by NTDETECT.COM. Windows NT enters the Windows load phases.