Windows Server 2012 Overview : Boot Configuration (part 2) – Boot environment essentials, Managing startup and boot configuration

Windows Server 2012 supports several different processor architectures and several different disk partitioning styles. EFI was originally developed for Itanium-based computers. Computers with EFI use the GUID partition table (GPT) disk type for boot and system volumes. Computers based on x86 use BIOS and the master boot record (MBR) disk type for boot and system volumes. Computers based on x64 use UEFI wrapped around BIOS or EFI.

With the increasing acceptance and use of UEFI and the ability of Windows to use both MBR and GPT disks regardless of firmware type, the underlying chip architecture won’t necessarily determine which firmware type and disk type a computer uses for boot and startup. That said, generally, BIOS-based computers use MBR for booting or for data disks and GPT only for data disks. EFI-based computers can have both GPT and MBR disks, but you typically must have at least one GPT disk that contains the EFI system partition (ESP) and a primary partition or simple volume that contains the operating system for booting.

With early releases of the server operating system for Windows, BIOS-based computers use Ntldr and Boot.ini to boot into the operating system. Ntldr handles the task of loading the operating system, while Boot.ini contains the parameters that enable startup, including the identity of the boot partitions. Through Boot.ini parameters, you can add options that control the way the operating system starts, the way computer components are used, and the way operating system features are used.

On the other hand, with early releases of the server operating system for Windows, EFI-based computers use Ia64ldr.efi, Diskpart.efi, and Nvrboot.efi to boot into the operating system. Ia64ldr.efi handles the task of loading the operating system, while Diskpart.efi identifies the boot partitions. Through Nvrboot.efi, you set the parameters that enable startup.

Windows Server 2008 and later don’t use these boot facilities. Instead, they use a pre-operating system boot environment. Figure 1 provides a conceptual overview of how the boot environment fits into the overall computer architecture.

Figure 1. A conceptual view of how the boot environment works.

The boot environment is an extensible abstraction layer that allows the operating system to work with multiple types of firmware interfaces without requiring the operating system to be specifically written to work with these firmware interfaces. Within the boot environment, startup is controlled using the parameters in the BCD data store.

The BCD store is contained in a file called the BCD registry. The location of this registry depends on the computer’s firmware:

Entries in the BCD data store identify the boot manager to use during startup and the specific boot applications available. The default boot manager is the Windows Boot Manager. Windows Boot Manager controls the boot experience, and you can use it to choose which boot application is run. Boot applications load a specific operating system or operating system version. For example, a Windows Boot Loader application loads Windows Server 2012. Because of this, you can boot BIOS-based and EFI-based computers in much the same way.

The Startup And Recovery dialog box controls the basic options for the operating system during startup. You can use these options to set the default operating system, the time to display the list of available operating systems, and the time to display recovery options when needed. Whether you start a computer to different operating systems or not, you’ll want to optimize these settings to reduce the wait time during startup and, in this way, speed up the startup process.

You can access the Startup And Recovery dialog box by completing the following steps:

You can use the System Configuration utility (Msconfig.exe) to fine-tune the way a computer starts. Typically, you use this utility during troubleshooting and diagnostics. For example, as part of troubleshooting, you can configure the computer to use a diagnostic startup where only basic devices and services are loaded.

The System Configuration utility is available on the Tools menu in Server Manager. You can also start the System Configuration utility by pressing the Windows key, typing msconfig.exe in the Apps Search box, and pressing Enter. As shown in Figure 3, this utility has a series of tabs with options.

Use the General tab options to configure the way startup works. This tab is where you should start your troubleshooting and diagnostics efforts. Using these options, you can choose to perform a normal startup, diagnostic startup, or selective startup. After you restart the computer and resolve any problems, access the System Configuration utility again, select Normal Startup on the General tab, and then tap or click OK.

Figure 3. Perform a diagnostic or selective startup as part of troubleshooting.

Use the Boot tab options, shown in Figure 4, to control the way the individual startup-related processes work. You can configure the computer to start in one of various Safe Boot modes and set additional options, such as No GUI Boot. If after troubleshooting you find that you want to keep these settings, you can select the Make All Boot Settings Permanent check box to save the settings to the boot configuration startup entry.

Figure 4. Fine-tune the boot options.

Tapping or clicking the Advanced Options button on the Boot tab displays the BOOT Advanced Options dialog box shown in Figure 5. In addition to being able to lock PCI, detect the correct HAL, and enable debugging, you can use the advanced options to do the following:

Figure 5. Set advanced boot options as necessary to help troubleshoot specific types of problems.

If you suspect services installed on a computer are causing startup problems, you can quickly determine this by choosing a diagnostic or selective startup on the General tab. After you identify that services are indeed causing startup problems, you can temporarily disable services using the Services tab options and then reboot to see if the problem goes away. If the problem no longer appears, you might have pinpointed it. You can then permanently disable the service or check with the service vendor to see if an updated executable is available for the service. As shown in Figure 6, you disable a service by clearing the related check box on the Services tab.

Figure 6. Disable services to try to pinpoint the source of a problem.

Similarly, if you suspect applications that run at startup are causing problems, you can quickly determine this using the options on the Startup tab. You disable a startup application by clearing the related check box on the Startup tab. If the problem no longer appears, you might have pinpointed the cause of it. You can then permanently disable the startup application or check with the software vendor to see if an updated version is available.