Chapter 6: Registry and the System Boot Process

Overview

"Complexity increases the possibility of failure; a twin-engine airplane has twice as many engine problems as a single-engine airplane."

--Airplane rule
(THE JARGON FILE, VERSION 4.1.2)

If you knew what you will know when your candle was burnt low it would greatly ease your plight while your candle still burns bright

--P. Hein
Grooks

As mentioned in Chapter 1, the Windows Server 2003 registry plays an extremely important role, because it actually manages the whole configuration of your system. As in Windows NT/2000/XP, the registry information also manages the Windows boot process. A proper understanding of the registry data's influence on the system's startup will allow you to solve most startup problems, such as the inability to boot or incorrect operation on start up.

Note 

As we will see in this chapter, the Windows Server 2003 boot process closely resembles the Windows NT/2000/XP boot process. This is not surprising, since both Windows XP and Windows Server 2003 are built on the basis of the Windows NT/2000 kernel. However, there are several improvements in this area that will be emphasized later in this chapter. These include a logical prefetcher for faster booting, boot-loader improvements and operating-system-boot improvements.

The role played by the system registry should never be underestimated, since it is required even in the early phases of the boot process (in actuality, as soon as the operating-system loader starts executing). For example, if the loader can't find the \System hive necessary for loading the drivers (or the hive happens to be corrupt), you'll see an error message like the one shown at the beginning of Chapter 1:

   Windows could not start because the following file is missing    or corrupt:   \WINDOWS\SYSTEM32\CONFIG\SYSTEM   You can attempt to repair this file by Starting Windows .NET Standard   Server Setup using   the original Setup floppy disk of CD-ROM.      Select 'r' at the first screen to repair.

When Windows XP or Windows Server 2003 is up and running, the \System registry hive is visible under HKEY_LOCAL_MACHINE. This hive defines the loading order for all drivers installed in the system. Both the operating system loader (Ntldr) and I/O Manager access this hive.

Each driver installed in the system has its own key under HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services. Each of the driver keys, in turn, contains a Start value entry. The value assigned to this entry defines the phase during the system boot process during which the driver is loaded and initialized. We'll talk about the Start value in more detail later in the chapter.