# Chapter 19 - What Happens When You Start Your Computer

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This chapter describes what happens when you start a computer that has a Windows NT installed as one of the operating systems. In general, this chapter describes what happens at each step in the process when the computer successfully starts. Chapter 21, "Troubleshooting Startup and Disk Problems," discusses what you can do to isolate startup problems, and how to recover from them.

This chapter also describes dual-booting and triple-booting other operating systems, such as Windows 95 and MS-DOS. It provides information about the contents of the Boot.ini file on x86-based computers, and describes the firmware menus and how to use them on RISC-based computers.

### Starting Windows NT

This section describes the steps involved in the successful startup of Windows NT, which are the following:

• Power On Self Test (POST) processing

• Initial startup process

• Selecting the operating system

• Detecting hardware

• Selecting a configuration

• Initializing the Kernel

• Logging on

The order and the processing is somewhat different, depending upon the hardware platform (x86-based computer or RISC-based computer).

The startup process begins when you:

• Power on the computer.

• Click Shutdown and Restart on the Shutdown Computer dialog box.

• Select Shut Down from the Logon Information dialog box.

• Select Restart the computer from the Shut Down Windows dialog box.

When you see the Begin Logon dialog box, with the text Press Ctrl+Alt+Delete to log on, your computer has completed the loading of Windows NT, and has completed much of the initialization. However, startup is complete only when a user can successfully log on at the Begin Logon dialog box.

Windows NT might not start up or operate correctly if any hardware components do not initialize correctly. Startup fails if any of the files required to start Windows NT are not present in the correct folder, or if one of the files has been corrupted. Table 19.1 describes the files that x86-based computers and RISC-based computers use to start Windows NT.

x86-based file

Folder

RISC-based file

Folder

NTLDR

root of startup disk

\Os\<winnt>

Boot.ini

root of startup disk

no equivalent

Bootsect.dos

root of startup disk

no equivalent

Ntdetect.com

root of startup disk

no equivalent

Ntbootdd.sys (SCSI only)

root of startup disk

Ntoskrnl.exe

%systemroot%\ System32

Ntoskrnl.exe

%systemroot%\ System32

Hal.dll

%systemroot%\ System32

Hal.dll

\Os\<winnt>

no equivalent

*.pal files (Alpha-based computers)

\Os\<winnt>

SYSTEM key

%systemroot%\ System32\Config

SYSTEM key

%systemroot%\ System32\Config

device drivers

%systemroot%\ System32\Drivers

device drivers

%systemroot%\ System32\Drivers

#### Power On Self Test Processing

When you power on or restart a computer, it goes through its Power On Self Test (POST) routine, which determines:

• The amount of real memory.

• Whether the needed hardware components (such as the keyboard) are present.

Once the computer has run its POST routine, each adapter card with a BIOS runs its own POST routine. The computer and adapter card manufacturers determine what appears on the screen during the POST processing.

#### Initial Startup Process

The first sector on the hard disk is critical to the startup process. This sector contains the Master Boot Record and the Partition Table.

If the startup disk is a floppy disk, the first sector on the disk is the Partition Boot Sector.

For more information about the Master Boot Record, the system partition, and the Partition Boot Sector, see Chapter 17, "Disk and File System Basics."

##### Starting an x86-based Computer

After the POST on x86-based computers, the system BIOS attempts to locate the startup disk. If there is a floppy disk in drive A, the system BIOS uses drive A as the startup disk. If there is no disk in drive A, the system BIOS then checks the first hard disk that is powered up.

Note Some system BIOS versions enable the user to reconfigure the order in which it checks the floppy disks and hard disks for the startup disk.

When the hard disk is the startup disk, the system BIOS reads the Master Boot Record, and loads it into memory. The system BIOS then transfers execution to the Master Boot Record. The code in the Master Boot Record scans the Partition Table for the system partition. When the Master Boot Record finds the system partition, it loads sector 0 of the partition into memory, and executes it. Sector 0 on the system partition can be a utility or diagnostic program, or a Partition Boot Sector that contains startup code for an operating system. The Partition Boot Sector code starts the operating system in a manner defined by the operating system.

If there is no system partition on the first hard disk, the Master Boot Record displays errors such as the following:

• Invalid partition table

• Missing operating system

The section "Setting the System Partition (x86-based Computers)," presented later in this chapter, describes identifying and changing the system partition.

The Master Boot Record is generally operating system independent. For example, on x86-based computers, you use the same Master Boot Record to start Windows NT, Windows 95, MS-DOS, and Windows 3.1x.

However, the Partition Boot Sector is dependent on both the operating system and the file system. On x86-based computers, the Windows NT Partition Boot Sector is responsible for:

• Understanding enough of the file system in use to find NTLDR in the root folder. On a FAT volume, the Partition Boot Sector is typically one sector long. On an NTFS volume, it can be up to 16 sectors long, with the extra sectors containing enough file system code to find NTLDR.

• Starting execution of the boot loader.

On x86-based computers, the system partition must be on the first physical hard disk. The boot partition (the partition containing Windows NT operating system files) can be the same as the system partition, can be on a different partition on the same hard disk, or can even be on a different hard disk.

If the first hard disk does not contain the system partition that you want to use to start your computer, you need to power down the disk so that the system BIOS can access the correct disk.

For information about why you might want to use another hard disk as your startup disk, see Chapter 20, "Preparing for and Performing Recovery."

If there is a floppy disk in drive A, the system BIOS loads the first sector on the disk into memory. If the floppy is bootable, the first sector on the disk is the Partition Boot Sector. If the floppy disk is not bootable, you see errors such as:

Non-System disk or disk error
Replace and press any key when ready

##### Starting a RISC-based Computer

After a RISC-based computer completes the POST routine, the resident ROM firmware selects the startup disk by reading a boot precedence table from nonvolatile RAM (NVRAM). What the firmware does depends upon the platform (Alpha, PowerPC, or MIPS computer) and the information in the NVRAM. For example, to startup from the floppy disk, the NVRAM must define it as an alternate boot selection.

The NVRAM also defines the:

• Path to the boot partition.

• Folder that contains the operating system to start.

The system partition can be on any hard disk on RISC-based computers. You can use the Boot selection menu to set up or change the system partition. See "Manage Boot Selection Menu," presented later in this chapter, for more information about changing the firmware and NVRAM on RISC-based computers.

The system partition on a RISC-based computer must be formatted with the FAT file system. This is because the ARC standard requires that firmware have the following stub drivers built into it:

• SCSI miniport

• FAT file system

RISC-based computers go straight from the firmware into OSLOADER, which is the RISC-based computer's equivalent of NTLDR. Therefore, the firmware has to take over the functionality of the Partition Boot Sector, which means that the partition that has OSLOADER on it has to be FAT. Once OSLOADER loads, it has enough of the NTFS drivers built into it (just like NTLDR does) that it can access a %systemroot% folder on an NTFS partition.

##### Setting the System Partition (x86-based Computers)

On an x86-based computer, the system partition must contain the boot loader and other files that load the operating system. Windows NT Setup sets the partition into which it installs these files as the system partition, but there are situations in which you might want to use another.

When Windows NT is running, you can use Disk Administrator to set the system partition. You can also use the MS-DOS-based utility Fdisk to set the system partition. Only a primary partition can be used as a system partition. You cannot use a logical drive in the extended partition as a system partition. When you set a new system partition, both Disk Administrator and Fdisk clear the Boot Indicator field, if it was set for any other partition.

Note The Boot Indicator field in the Partition Table indicates whether a partition is the system partition.

###### To Use Disk Administrator to set the system partition
1. Click a primary partition or logical drive on the hard disk.

2. Click the Partition menu. If the partition is the system partition, or is a logical drive in an extended partition, the Mark Active command is not available.

3. If the partition is not the system partition, and you want to set it as the system partition, click the Mark Active command. Disk Administrator displays the following message box:

You cannot use Disk Administrator to set the system partition if you cannot start Windows NT. You can use the MS-DOS-based Fdisk utility to set the system partition, even if your entire disk is formatted with the NTFS file system.

###### To Use the Fdisk utility
1. Start the computer under MS-DOS. If you do not have a system partition on your first hard disk, you must start MS-DOS from a floppy disk.

2. At the command prompt, type fdisk.

3. The FDISK Options menu has several choices. Type 2 to see the Set Active Partition screen. The system partition is identified by an A in the Status column.

4. Type the number of the partition that you want to set as the system partition. Press ESC to return to the FDISK Options menu, and press ESC again to exit Fdisk.

The boot loader enables you to select the operating system that you want to start, and loads the operating system files from the boot partition. Boot loader processing is different on x86-based and RISC-based computers.

##### NTLDR Functions (x86-based Computer)

NTLDR controls the operating system selection process and hardware detection prior to the Windows NT Kernel initialization. NTLDR must be in the root folder of your startup disk, and also requires that the following files be located in the root folder:

• Ntdetect.com

• Boot.ini

• Bootsect.dos (if dual-booting)

• Ntbootdd.sys (if using the scsi() syntax in the Boot.ini file)

If the path name in the Boot.ini file for your system partition uses the scsi() syntax, the file Ntbootdd.sys must be in the root folder of the system partition. For more information about the scsi() syntax and Ntbootdd.sys, see Chapter 20, "Preparing for and Performing Recovery."

When NTLDR starts executing, it clears the screen and displays the boot loader message, which is:

OS Loader V4.0


NTLDR then performs the following steps:

• Switches the processor into the 32-bit flat memory mode. When x86-based computers first start, they are running in real mode, like an 8088 or 8086 CPU. Because NTLDR is mostly a 32-bit program, it must switch the processor to 32-bit flat memory mode before it can perform any other functions.

• Starts the appropriate minifile system. The code to access files on FAT and NTFS volumes is built into NTLDR. This code enables NTLDR to read, access, and copy files.

• Reads the Boot.ini file, and displays the operating system selections. This screen is referred to as the boot loader screen.

• Allows the user to select an operating system from the boot loader screen.

• If the user selects an operating system other than Windows NT, NTLDR loads Bootsect.dos and passes control to it. The other operating system then starts up as normal, because Bootsect.dos contains the Partition Boot Sector that was on the primary partition or logical drive before you installed Windows NT.

• If you select a Windows NT version, NTLDR executes Ntdetect.com to gather information about currently installed hardware.

• NTLDR presents you with the choice of starting the computer in the configuration in use when Windows NT was last shutdown (Default), or the Last Known Good configuration. You have this option only if you press the space bar when prompted, or you have more than one hardware profile. You have approximately five seconds to select this option.

• NTLDR loads and starts Ntoskrnl.exe. NTLDR passes the hardware information collected by Ntdetect.com to Ntoskrnl.exe.

On RISC-based computers, Osloader.exe performs all of the functions that are performed by the x86-based components NTLDR, Ntdetect.com, and Bootsect.dos.

The NVRAM contains environment variables that provide the functional equivalent of the Boot.ini file on x86-based computers.

#### Selecting the Operating System to Start

The boot loader displays the screen from which you select the operating system to start. The information on the screen is different for x86-based computers and RISC-based computers.

##### Boot Loader Screen (x86-based Computer)

NTLDR displays a menu from which you select the operating system to start. This screen is based upon the information in the Boot.ini file. The screen looks like this:

OS Loader V4.0

Please select the operating system to start:

Windows NT Workstation Version 4.0
Windows NT Workstation Version 4.0 (VGA mode)
MS-DOS

Use [up] and [down] to move the highlight to your choice.
Press Enter to choose.

Seconds until highlighted choice will be started automatically: 29


If you do not select an entry before the counter reaches zero, NTLDR loads the operating system specified by the default parameter in the Boot.ini file. Windows NT Setup sets the default entry to the most recent copy of Windows NT that you installed. You can edit the Boot.ini file to change the default entry if you want to default to an operating system other than the most recently installed version of Windows NT.

For information about changing the Boot.ini file, see "Contents and Purpose of Boot.ini," presented later in this chapter.

The Boot menu contains the boot options. The first selection is always the default operating system, which is the most recently installed version of Windows NT unless you change the order of the boot selections.

To change the default operating system, or add or change boot selections , see the section titled "Manage Boot Selection Menu," presented later in this chapter.

This is a sample Boot menu from an Alpha-based computer:

ARC Multiboot Alpha AXP Version 3.5-11
Copyright (c) 1993 Digital Equipment Corporation

Boot Windows NT Workstation Version 4.0
Boot an alternate operating system
Run a program

Use the arrow keys to select, then press Enter.
Seconds until auto-boot. Select another option to override: 9


The first line on the Boot menu is highlighted. Pressing ENTER begins startup of the default operating system.

If you have included alternate boot selections in your NVRAM, you can select Boot an alternate operating system, which results in a screen like the following.

ARC Multiboot Alpha AXP Version 3.5-11
Copyright (c) 1993 Digital Equipment Corporation

Boot Windows NT Workstation 4.0 (Default)
Boot Windows NT Workstation 3.51
Boot SCO Unix v7.2

Use the arrow keys to select, then press Enter.


#### Detecting Hardware

On RISC-based computers, Osloader.exe obtains the hardware information from the firmware.

Ntdetect.com is the hardware detector for x86-based computers. It collects a list of currently installed components and returns this information to NTLDR.

On x86-based computers, Ntdetect.com executes after you select a Windows NT operating system on the boot loader screen (or the timer times out). When Ntdetect.com begins to execute, you see the following line on the screen:

NTDETECT V1.0 Checking Hardware . . .


Ntdetect.com detects the following components:

• Computer ID

• Video

• Keyboard

• Communication Ports

• Parallel Ports

• Floppy Disks

• Mouse/Pointing Device

#### Selecting a Configuration

When you have selected the version of Windows NT to start, and the boot loader has collected hardware information, you see the following screen:

OS Loader V4.0

Press spacebar now to invoke Hardware Profile/Last Known Good menu.


The boot loader waits a few seconds for you to press the SPACEBAR. If you do not press the SPACEBAR, and you have only one hardware profile, the boot loader loads Windows NT by using the Default control set. Otherwise, you see this screen:

Hardware Profile/Configuration Recovery Menu

This menu allows you to select a hardware profile
to be used when Windows NT is started.

If your system is not starting correctly, then you may switch to a
previous system configuration, which may overcome startup problems.
IMPORTANT: System configuration changes made since the last successful

Original Configuration
some other hardware profile

Use the up and down arrow keys to move the highlight
to the selection you want. Then press ENTER.
To switch to the Last Known Good Configuration, press 'L'.

Seconds until highlighted choice will be started automatically: 5


The first hardware profile is highlighted. If you have created other hardware profiles, use the down arrow to select the one that you want to use. For more information about hardware profiles, use the Find tab in Windows NT Help and enter profile.

You can also select between the Last Known Good Configuration and the Default Configuration. Windows NT automatically uses the Default Configuration if you do not select the Last Known Good Configuration. When you use the Default Configuration, the boot loader uses the Registry information that Windows NT saved at the last shutdown.

If you switch to the Last Known Good Configuration by pressing L and ENTER, the boot loader uses the Registry information that it saved at the completion of the last successful startup to configure this startup.

When you press ENTER on the Hardware Profile/Configuration Recovery menu or the boot loader automatically makes the selection for you, the computer is in the Kernel load phase of Windows NT startup. You see several dots as the boot loader loads the Windows NT Kernel (Ntoskrnl.exe) and the hardware adaption layer (Hal.dll) into memory. It does not initialize these programs yet. Next, the boot loader loads the Registry key HKEY_LOCAL_MACHINE \SYSTEM from %systemroot%\System32\Config\System.

At this point, the boot loader creates the control set it will use to initialize the computer. The value in the HKEY_LOCAL_MACHINE \SYSTEM \Select subkey determines which control set in HKEY_LOCAL_MACHINE \SYSTEM to use. The loader uses the control set identified by the Default value, unless you are starting by using the Last Known Good Configuration. In this case, the value under LastKnownGood specifies the control set. Based on your selection and the value of the corresponding Select subkey, the loader determines which ControlSet00x to use. It sets the value of Current in the Select subkey to the number of the control set it will use.

See "Control Sets in the Registry," presented later in this chapter, for more information about the Select subkey and control sets.

At this time, the boot loader scans all of the services in the Registry subkey HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Services for device drivers with a Start value of 0x0, which indicates that they should be loaded but not initialized. Device drivers with these values are typically low-level hardware device drivers, such as hard disk device drivers. The Group value for each device driver determines the order in which the boot loader loads them. The Registry subkey HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Control ServiceGroupOrder defines the loading order.

On x86-based computers, the loading of these device drivers into memory is done using BIOS INT 13 calls in real mode (or by Ntbootdd.sys).

On RISC-based computers, OSLOADER calls firmware primitives to find and load the critical files into memory.

The Windows NT Workstation Resource Kit CD contains more information about the Registry in the Help file Regentry.hlp. When you install the Resource Kit, double-clicking the Registry Help File icon opens the Regentry.hlp.

#### Initializing the Kernel

You know that the Kernel is initializing when the screen turns blue, and you see text similar to the following:

Microsoft (R) Windows NT (TM) Version 4.0 (Build 1345)
1 System Processor (16 MB Memory)


This means that Ntoskrnl.exe has successfully initialized and that control has passed to it.

The Kernel creates the HKEY_LOCAL_MACHINE \HARDWARE key by using the information that was passed from the boot loader. This key contains the hardware data that is computed at each system startup. The data include information about hardware components on the system board and about the interrupts hooked by specific hardware devices.

The Kernel creates the Clone control set by making a copy of the control set pointed to by the value of Current. The Clone control set is never modified, because it is intended to be an identical copy of the data used to configure the computer and should not reflect any changes made during the startup process.

The Kernel now initializes the low-level device drivers that were loaded during the Kernel load phase. If an error occurs, the action taken is based on the HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \ServicesDriverName\ErrorControl value for the device driver that has a problem. See the section titled "ErrorControl Values," presented later in this chapter, for more information.

Ntoskrnl.exe now scans the Registry, this time for device drivers that have a HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \ServicesDriverName\Start value of 0x1. As in the Kernel load phase, the Group value for each device driver determines the order in which they are loaded. The Registry subkey HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Control \ServiceGroupOrder defines the loading order.

Unlike the Kernel load phase, device drivers with a Start value of 0x01 are not loaded by using BIOS or firmware calls, but by using the device drivers loaded during the Kernel load phase and just initialized. The device drivers in this second group are initialized as soon as they are loaded. Error processing for the initialization of this group of device drivers is also based on the value of the ErrorControl data item for the device driver.

The Session Manager (Smss.exe) starts the higher-order subsystems and services for Windows NT. Information for the Session Manager is in HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Control \Session Manager. Session Manager executes the instructions under the:

• BootExecute data item.

• Memory Management key.

• DOS Devices key.

• Subsystems key.

###### BootExecute Data Item

The BootExecute data item contains one or more commands that Session Manager runs before it loads any services. The default value for this item is Autochk.exe, which is the Windows NT version of Chkdsk.exe. The default setting is shown in this example:

BootExecute : REG_MULTI_SZ : autocheck autochk*


Session Manager can run more than one program. This example shows the item when the Convert utility will be run to convert the x volume from FAT to NTFS on the next system startup:

BootExecute : REG_MULTI_SZ : autocheck autochk* autoconv \DosDevices\x: /FS:ntfs


After Session Manager runs the commands, the Kernel loads the other Registry keys from %systemroot%\System32\Config.

###### Memory Management Key

Next, the Session Manager creates the paging information required by the Virtual Memory Manager. The configuration information is located in these data items:

PagedPoolSize : REG_DWORD 0
NonPagedPoolSize : REG_DWORD 0
PagingFiles : REG_MULTI_SZ : c:\pagefile.sys 32


For information about the page file, use the Index tab in Windows NT Help, and enter virtual memory.

###### DOS Devices Key

Next, the Session Manager creates symbolic links. These links direct certain classes of commands to the correct component in the file system. The configuration information for these default items is located in:

PRN : REG_SZ : \DosDevices\LPT1
AUX : REG_SZ : \DosDevices\COM1
NUL : REG_SZ : \Device\Null
UNC : REG_SZ : \Device\Mup
PIPE : REG_SZ : \Device\NamedPipe
MAILSLOT : REG_SZ : \Device\MailSlot

###### SubSystems Key

Because of the messaging architecture of subsystems, the Windows subsystem (Win32) must be started. This subsystem controls all I/O and access to the video screen. The process name for this subsystem is CSRSS. The Windows subsystem starts the WinLogon process, which then starts several other vital subsystems.

The configuration information for required subsystems is defined by the value for Required in the Registry subkey HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Control \Session Manager\SubSystems.

#### Logging on

The Windows subsystem automatically starts Winlogon.exe, and Winlogon.exe starts the Local Security Administration (Lsass.exe). You now see the Begin Logon dialog box, which contains the text Press Ctrl+Alt+Delete to log on. At this time, Windows NT might still be initializing network device drivers, but you can logon now.

Next the Service Controller (Screg.exe) executes, which makes a final pass through the Registry looking for services that are marked to load automatically. Auto-load services have a Start value of 0x2 in the subkeys HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \ServicesDriverName.The services that are loaded during this phase are loaded based on their dependencies, because they are loaded in parallel. The dependencies are described in the DependOnGroup and DependOnService entries in the subkey HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \ServicesDriverName.

Note Windows NT startup is not considered good until a user successfully logs on to the system. After a successful logon, the Clone control set is copied to the LastKnownGood control set.

### Configuring the Computer for Dual-booting and Triple-booting

This section describes how to start up multiple operating systems and contains procedures for configuring your computer to do so.

Each operating system uses one or more file systems to organize data within volumes. Some operating systems can use the same file systems and some can not. For example, MS-DOS, Windows 95, and Windows NT can each use FAT volumes; Windows NT and Unix each use file systems that are unusable by the other. Operating systems that use the same file systems can share volumes, meaning that a user can access files on these volumes when running any of the operating systems.

Note Create an Emergency Repair Disk for your Windows NT installation by using the Repair Disk utility (Rdisk.exe) in the %systemroot%\System32 folder before you install other operating systems on the computer. You should also have a Windows NT startup floppy disk that you know works to start your computer. For more information about these disks, see Chapter 20, "Preparing for and Performing Recovery."

#### Using More Than One Windows Operating System

Windows 95, Windows 3.1, or Windows 3.11 can reside on the same computer as Windows NT. Windows NT can be installed in the same folder as Windows 3.1 or Windows 3.11 because Windows NT puts all of its important files in the system32 folder. Windows NT only uses the %systemroot% folder for legacy ini files that it maintains for 16-bit application programs and backwards compatibility. So, all of the Windows 3.1 or Windows 3.11 files will be either in the %systemroot% folder or in the %systemroot%\System folder. This organization allows the two operating systems to co-exist in the same folder.

You can also install Windows NT into a different folder. Windows 3.1 or Windows 3.11 still co-exist with Windows NT, but you do not get the option to migrate ini and program manager settings from Windows 3.1 or Windows 3.11.

If you install Windows 95 and Windows NT on the same disk, you must install them in different folders.

You can also install different versions of the Windows NT operating system on your hard disk, as long as you install them on different folders. If you are going to log into a domain, each instance of Windows NT must have a different computer name, which you specify during Windows NT Setup. You should ask your network administrator for the computer name to use before running Windows NT Setup.

When you install multiple Windows operating systems on the same computer, you need to install Windows-based application programs by using each operating system. For example, if you install both Windows 95 and Windows NT 4.0, you need to install application programs when you are running Windows NT 4.0 and when you are running Windows 95. If you have more than one version of Windows NT installed, you also need to install the application programs when running each version. To install Windows-based application programs when running Windows NT 4.0, you must log on with a user ID that has administrative privileges.

#### Dual-booting on x86-based Computers

When your system partition contains the Windows NT Partition Boot Sector, Windows NT supports dual-booting between one or more instances of Windows NT and one additional operating system. The additional operating systems that are currently supported are MS-DOS, Windows 95, and OS/2, versions 1.1 and 1.3. OS/2 versions 2.x might work, but are not supported.

You can also triple-boot Windows NT, Windows 95, and MS-DOS. You can install and start up other operating systems from your hard disk, but you need to change the system partition. For procedures to change the system partition, see "Setting the System Partition," presented earlier in this chapter.

When you install a Windows NT operating system on an x86-based computer, Windows NT Setup copies the first sector of the system partition (the Partition Boot Sector) to a file named Bootsect.dos. It then replaces the Partition Boot Sector with its own Partition Boot Sector.

When you start your computer and the system partition contains the Windows NT Partition Boot Sector, the code in the Partition Boot Sector loads the Windows NT boot loader, NTLDR. The boot loader screen enables you to choose which Windows NT installation to start, or to start another operating system that is defined on the boot loader screen.

If you select an operating system other than Windows NT from the boot loader screen, NTLDR loads and starts the Bootsect.dos file. This functionality results in the other operating system starting as if NTLDR had not intervened. In the case of MS-DOS, the Bootsect.dos code looks for IO.sys; in the case of OS/2, the Bootsect.dos code looks for Os2ldr.exe.

##### Configuring for Windows NT and MS-DOS

You can dual-boot between Windows NT and MS-DOS on an x86-based computer.

Configuring your computer is easier if you install MS-DOS before you install Windows NT. If you decide to install MS-DOS after you have installed Windows NT, MS-DOS overwrites the Windows NT information in the Partition Boot Sector with its own information. You should have a current Emergency Repair Disk for the computer on which you are installing MS-DOS.

If you have already installed Windows NT and want to install MS-DOS, use one of the following procedures. After you install MS-DOS, you will need to replace the MS-DOS Partition Boot Sector with the Windows NT Partition Boot Sector.

###### To Install MS-DOS from floppy disks
1. Boot from the A drive. The MS-DOS Setup program executes. Install MS-DOS following the instructions in the program.

2. When MS-DOS Setup completes, remove the floppy disk from the A drive.

3. Restore the Windows NT Partition Boot Sector by using the procedure described later in this section.

4. When you restart after replacing the Partition Boot Sector, you have a dual-boot computer.

###### To Install MS-DOS from the network
1. Install MS-DOS from the network by executing Setup.exe.

2. When MS-DOS Setup completes, restore the Windows NT Partition Boot Sector by using the procedure described later in this section.

3. When you restart after the replacing the Partition Boot Sector, you have a dual-boot computer.

After you install MS-DOS, you need to replace the MS-DOS Partition Boot Sector with the Windows NT one. To be able to dual-boot MS-DOS, you also need to create the file Bootsect.dos. The next procedure does both of these things.

###### To Restore the Windows NT Partition Boot Sector
1. Start up the computer from the Windows NT Setup disk 1. Follow the instructions to insert disk 2. When Windows NT Setup asks what you want to do, select the option to Repair by pressing the R key. Windows NT Setup displays the following options:

[X] Inspect registry files
[X] Inspect startup environment
[X] Verify Windows NT system files
[X] Inspect boot sector

2. Clear all selections except the last one, Inspect boot sector. Select Continue (perform selected tasks) and press ENTER.

3. Insert Setup Disk 3 when prompted.

4. You are prompted for the Emergency Repair Disk. Setup displays the following messages after it has finished processing the Emergency Repair Disk:

Setup has completed repairs.
If there is a floppy disk inserted in drive A:, remove it.
Press ENTER to restart your computer.


When you restart the computer, you can select a Windows NT installation or MS-DOS from boot loader screen.

After you have installed MS-DOS and replaced the Partition Boot Sector, it is a good idea to make a MS-DOS bootable floppy disk. This floppy disk should include the MS-DOS files, as well as the Master Boot Record and Partition Boot Sector for each boot partition. See "MS-DOS Bootable Floppy Disk" in Chapter 20, "Preparing for and Performing Recovery," for information about creating this disk.

##### Configuring for Windows NT and Windows 95

You can configure your computer to start either of these two operating systems. Currently, your installations are easier and less error-prone if you install Windows 95 first and then install Windows NT. This order is recommended because sometimes Windows 95 replaces a Windows NT Partition Boot Sector with its own Partition Boot Sector. A Windows 95 Partition Boot Sector causes a problem for NTFS volumes, because the Windows 95 Partition Boot Sector is for a FAT partition. Windows NT can no longer access the NTFS volume. If you install Windows 95 first, use the installation procedures provided with the Windows 95 CD-ROM.

If you want to be able to triple-boot Windows 95, Windows NT, and MS-DOS, you should install MS-DOS first, as described in "Triple-booting Windows NT, Windows 95, and MS-DOS," presented later in this chapter.

If you have Windows NT installed, and want to be able to install and dual-boot Windows 95, you must configure Windows NT to dual-boot with MS-DOS. See "Configuring for Windows NT and MS-DOS," presented earlier in this chapter, for the procedures to install MS-DOS if you do not already have it installed. Then use the procedures described in "Triple-booting Windows NT, Windows 95, and MS-DOS," presented later in this chapter.

##### Configuring for Windows NT, Windows 95, and MS-DOS

On an x86-based computer, you can configure your computer to triple-boot one of these three operating systems. You should install them in the following order:

• MS-DOS

• Windows 95

• Windows NT

Install each of these operating systems using their standard installation procedure. To start Windows NT, select the instance to start on the boot loader screen. You can also select Windows 95 from the boot loader screen.

To start MS-DOS, first select Windows 95 from the boot loader screen. Select ENTER on the screen, and press either the F4 or the F8 key. When you press F8, Windows 95 displays its Startup menu. Select Previous version of MS-DOS to start MS-DOS. Using the F4 key bypasses the Windows 95 Startup menu and starts MS-DOS directly.

Another way to be able to start all three of these operating systems is to configure your computer for a dual-boot of Windows NT and Windows 95, and start MS-DOS from an MS-DOS bootable floppy disk.

If you install Windows 95 in an existing Windows folder rather than doing a clean install, you need to edit Msdos.sys to enable Windows 95 to dual-boot MS-DOS. Do this by making the file visible, and then turning off the read only attribute. You can then change the file.

###### To Enable startup of MS-DOS from Windows 95
1. On the View menu of My Computer or Windows NT Explorer, click Options.

2. On the Options tab, select Show all files. Click OK.

3. Find Msdos.sys and click the filename.

4. On the File menu, click Properties.

5. In the Attributes box of the General tab, clear the Read Only and Hidden check boxes, and then click OK.

6. Using a text editor, such as Notepad, add the following line to the [Options] section of Msdos.sys:

BootMulti=1

If you upgrade or reinstall Windows 95, Setup deletes any of these files that it finds in your MS-DOS folder and replaces them with the Windows 95 versions in the Windows95 folder and Windows95\Command folder:

 Ansi.sys Doskey.com Keyb.com Ramdrive.sys Attrib.sys Drvspace.bin Keyboard.sys Readme.txt Chkdsk.exe Drvspace.exe Label.exe Scandisk.exe Choice.com Drvspace.sys Mem.exe Scandisk.ini Country.sys Edit.com Mode.com Server.exe Dblspace.bin Edit.hlp More.com Share.exe Dblspace.exe Ega.cpi Move.exe Smartdrv.exe Dblspace.sys Emm386.exe Mscdex.exe Sort.exe Debug.exe Fc.exe Msd.exe Start.exe Defrag.exe Fdisk.exe Networks.txt Subst.exe Deltree.exe Find.exe Nlsfunc.exe Sys.com Diskcopy.exe Format.com Os2.txt Xcopy.exe Display.sys Help.com

If you already have a dual-boot configuration of Windows NT and MS-DOS, you can install Windows 95 by using the following procedure. You should have a current Emergency Repair Disk for your Windows NT installation(s).

###### To Install Windows 95 on a Windows NT/MS-DOS dual-boot configuration
1. Shut down Windows NT and restart your computer. Select MS-DOS from the boot loader screen.

2. Install Windows 95. Make sure you install Windows 95 to a separate folder, and not the Windows NT %systemroot% folder.

After you successfully install Windows 95 and restart the computer, the Windows NT boot loader screen should appear and you can choose between Windows NT and Windows 95. Windows 95 is the first entry on the screen. If you want to make Windows NT the default, see "Contents and Purpose of Boot.ini," presented later in this chapter, for information about changing the order of the selections.

If the Windows NT boot loader screen does not appear, restore the Windows NT Partition Boot Sector by using the procedure in "Dual-booting Windows NT and MS-DOS," presented earlier in this chapter.

Note If you do not install Windows 95 on the C drive, Windows 95 Setup creates a hidden, read only folder on your C drive that has the same name as the folder into which you are installing Windows 95.

##### Configuring for a Multi-boot With OS/2

If you want to install OS/2, this is the order in which you should install the operating systems:

• MS-DOS

• Windows 95

• Windows NT

• OS/2

This is the safest order in which to install all four operating systems. MS-DOS, Windows 95, and Windows NT all have to share a system partition (C:), but can be installed on their own individual partition. They can also be installed in the same partition, but Windows 95 and Windows NT must be installed in different folders. OS/2 requires its own primary partition on the first hard disk, and also requires a second, small primary partition for the BOOTLOADER.

If done correctly, the startup sequence will be:

1. The OS/2 bootloader loads, and you have the choice of starting from the OS/2 partition, or starting from the MS-DOS/Windows 95/Windows NT system partition.

2. When the Windows NT boot loader loads, you can select from one or more versions of Windows NT or Windows 95.

3. If you select Windows 95, you can press F8 and get the Windows 95 Startup menu, which allows you to start Windows 95, the Windows 95 command prompt only, or the previous version of MS-DOS.

The above sequence work if you install fewer than the four operating systems.

#### Dual-booting on RISC-based Computers

On RISC-based computers, you can install and dual-boot multiple versions of Windows NT, and you can also install and startup Unix. The Setup program for the operating system being installed updates the NVRAM with information for starting the operating system. The last operating system installed sets the NVRAM to have itself as the default operating system to start. See the section "Manage Boot Selection Menu," presented later in this chapter for information on changing the default operating system.

### Control Sets in the Registry

A control set contains system configuration information, such as which device drivers and services to load and start. Control sets are stored in the Registry as subkeys of HKEY_LOCAL_MACHINE \SYSTEM. There can be several control sets, depending on how often you change system settings or have problems with the settings you choose. A typical installation of Windows NT contains these control set subkeys:

• Clone

• ControlSet001

• ControlSet002

• ControlSet003

• CurrentControlSet

The CurrentControlSet subkey is a pointer to one of the ControlSet00x keys. The Clone control set is a clone of the control set used to initialize the computer (either Default or LastKnownGood), and is created by the Kernel initialization process each time you start your computer. The Clone control set is not available after a user logs on.

In order to better understand how these control sets are used, you should know about the Registry subkey HKEY_LOCAL_MACHINE \SYSTEM \Select, which contains the following values:

• Current

• Default

• Failed

• LastKnownGood

Each of these values contain a REG_DWORD data type, which refers to a specific control set. For example, if the Current value is set to 0x1, then CurrentControlSet is pointing to ControlSet001. Similarly, if LastKnownGood is set to 0x2, then the Last Known Good control set is ControlSet002. The Default value is usually the same value as Current. Failed is the control set that was pointed to by Default when a user last started the computer by using the LastKnownGood control set.

The section titled "Selecting the Configuration to Use," presented earlier in this chapter, describes initializing Windows NT by using either the Default configuration or the LastKnownGood configuration. When you select the Default configuration, the Kernel uses the value of Default to determine which control set to use.

There are only two times when the Kernel attempts to load the LastKnownGood configuration:

• You select the Last Known Good Configuration from the Hardware Profile/Last Known Good menu.

Starting by using the LastKnownGood control set provides a way to recover from problems such as:

• A device driver added to the system since the last startup is causing problems.

• User-modified value entries in the Registry prevent the computer from starting up.

The LastKnownGood option is useful only in cases of incorrect configurations. It does not solve problems caused by corrupted or missing device drivers or files.

Important If you select the Last Known Good Configuration, any configuration changes made during the last system boot are lost.

Once you have logged on, the CurrentControlSet is that one that is changed whenever you make changes to your configuration by using options in Control Panel. If you are manually editing a control set for some reason, the CurrentControlSet is the only one that you should change.

If you are not sure where to look under the CurrentControlSet for a particular key, you can use Find Key on the View menu of the Windows NT Registry Editor. Each control set contains two subkeys: Control and Services. Control contains miscellaneous system information, such as the size and location of the page file. Services contains device driver information, such as file system drivers, Kernel drivers, and status information for each.

Note There are two Registry Editor programs on the Windows NT Workstation product CD, Regedt32.exe and Regedit.exe. You can use either one to view the Registry.

#### Start Values

There is a Start value for each Services subkey in the Registry key HKEY_LOCAL_MACHINE \SYSTEM<control set>\Services\DriverName. It specifies the starting values for the device or service, as follows:

• 0x0 (Boot) = Loaded by boot loader (NTLDR or OSLOADER) before the Kernel is initialized. Disk device drivers are examples of device drivers that use this value.

• 0x1 (System) = Loaded by the I/O subsystem during Kernel initialization. The mouse device driver is an example of a device driver that uses this value.

• 0x2 (Auto load) = Loaded by Service Control Manager. To be loaded or started automatically for all startups, regardless of service type. The parallel port device driver is an example of a device driver with a value of auto load. The Alerter service is one of the services that uses this value.

• 0x3 (Load on demand) = Loaded by Service Control Manager only when explicitly instructed to do so. Available, regardless of type, but it is not be started until the user starts it (for example, by using the Devices option in Control Panel).

• 0x4 (Disabled) = Do not load. Windows NT sets device drivers to disabled when Service Control Manager should not load them, such as when the corresponding hardware is not installed. Having this value means that the device drivers are not loaded by Service Control Manager. File system drivers are the one exception to the Start value. They are loaded even if they have a start value of 4. If a device driver is accidentally disabled, reset this value by using the Services option in Control Panel.

Note You can view the Start value of device drivers by using the Devices option in Control Panel.

#### ErrorControl Values

These are the possible ErrorControl values in the Registry key HKEY_LOCAL_MACHINE \SYSTEM<control set>\Services\DriverName:

• Ignore (value 0x0) — If the device driver fails to load or initialize, startup continues with no warning message.

• Normal (value 0x1) — If the device driver or service fails to load or initialize, startup continues after displaying a warning message. Most device drivers and services have ErrorControl set to this value.

• Severe (value 0x2) — When the Kernel detects an error in this device driver or service, it switches to the LastKnownGood control set, and the startup process starts again. If the control set being used is already LastKnownGood, the error is ignored and processing continues.

• Critical (value 0x3) — The same procedure as Severe is used, with the exception that if the LastKnownGood control set is already being used, the startup process stops, and a failure error message is displayed.

### Contents and Purpose of Boot.ini (x86-based Computers)

When you install Windows NT on an x86-based computer, Windows NT Setup puts the Boot.ini file at the root of the system partition. NTLDR uses information in the Boot.ini file to display the screen from which you select the operating system to start.

Here is a sample Boot.ini file:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation
Version 4.0"
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation
Version 4.0 [VGA mode]" /basevideo /sos
C:\="Windows 95"


The Boot.ini file has two sections, [boot loader] and [operating system], which are described in the next two sections.

This section contains the following information:

Parameter

Description

timeout

The number of seconds the user has to select an operating system from the boot loader screen before NTLDR loads the default operating system.
If the value is 0, NTLDR immediately starts the default operating system without displaying the boot loader screen.
You can also set this value to -1, in which case NTLDR waits forever for you to make a selection. You must edit the Boot.ini file to set the value to -1, because it is an illegal value for the System option in Control Panel.

default

The path to the default operating system.

#### [operating systems] Section

This section contains the list of available operating systems. Each entry includes the path to the boot partition for the operating system, the string to display in the boot loader screen, and optional parameters. There is an example of the use of this section of the Boot.ini file in the section titled "Boot Loader Screen (x86-based Computers)," presented earlier in this chapter.

The Boot.ini file supports starting of multiple versions of Windows NT operating systems, as well as starting one other operating system. The other operating systems that can be included in the Boot.ini file are Windows 95, MS-DOS, and OS/2. The section "Configuring the Computer for Dual-booting and Triple-booting," presented earlier in this chapter, contains more information about the other operating systems.

#### Boot.ini Switches

There are several switches that you can add to the end of the Windows NT entries in the [operating system] section of the Boot.ini file. They are not case sensitive. Chapter 21, "Troubleshooting Startup and Disk Problems," contains more information about many of these switches. For information about the debugger, see Chapter 39, "Windows NT Debugger."

Switch

Description

/BASEVIDEO

The computer starts up using the standard VGA video driver. If you have installed a new video driver, but it is not working correctly, selecting the Windows NT entry with this switch enables you to start the computer so you can change to a different driver.

/BAUDRATE=nnnn

Specifies the baud rate to be used for debugging. If you do not set the baud rate, the default baud rate is 9600 if a modem is attached, and 19200 for a null-modem cable. This switch has a secondary effect of forcing the /DEBUG switch as well, whether or not use you use /DEBUG.

/CRASHDEBUG

The debugger is loaded when you start Windows NT, but remains inactive unless a Kernel error occurs. This mode is useful if you are experiencing random, unpredictable Kernel errors.

/DEBUG

The debugger is loaded when you start Windows NT, and can be activated at any time by a host debugger connected to the computer. This is the mode to use when you are debugging problems that are regularly reproducible.

/DEBUGPORT= comx

Specifies the com port to use for debugging, where x is the communications port that you want to use. Like /BAUDRATE, this switch will also force the /DEBUG mode.

/MAXMEM:n

Specifies the maximum amount of RAM that Windows NT can use. This switch is useful if you suspect a memory chip is bad. See Chapter 21, "Troubleshooting Disk and Startup Problems," for more information.

/NODEBUG

No debugging information is being used.

/NOSERIALMICE=[COMx | COMx,y,z...]

Disables serial mouse detection of the specified COM port(s). Use this switch if you have a component other than a mouse attached to a serial port during the startup sequence. If you use /NOSERIALMICE without specifying a COM port, serial mouse detection is disabled on all COM ports. See Chapter 20, "Preparing for and Performing Recovery," for more information.

/SOS

Displays the device driver names while they are being loaded. Use this switch if Windows NT won't start up and you think a device driver is missing. See Chapter 21, "Troubleshooting Disk and Startup Problems," for more information.

#### Editing Boot.ini

When you install Windows NT, the Boot.ini file has the Read Only, System, and Hidden attributes set. You can edit the timeout and default parameters in the Boot.ini file by using the System option on Control Panel, regardless of the value of these attributes.

If you want to edit the Boot.ini file by using a text editor, you need to make the file visible before you can open it, and you need to turn off Read Only to be able to make changes to it. You can change the attributes by using My Computer, Windows NT Explorer, or the command prompt.

##### To change the attributes in My Computer or Windows NT Explorer
1. On the View menu, click Options.

2. On the Options tab, select Show all files. Click OK.

3. Click the filename.

4. On the File menu, click Properties.

5. In the Attributes box of the General tab, clear the Read Only, System, and Hidden check boxes, and then click OK.

To change the attributes by using command prompt, enter:

attrib -s -h -r boot.ini

If you change the path to the Windows NT boot partition, make sure to edit both the default path and operating system path entries. If you change one but not the other, a new choice is added to the boot loader screen, with the default designator next to it.

### Using a RISC-based Computer's Boot Menu

This section describes using the firmware menus on a RISC-based computer to change environment information in the NVRAM. There are three types of RISC-based computers: Alpha, MIPS, and PowerPC. The examples in this section are for an Alpha AXP-based computer, running firmware version 3.5-11. Menus for other versions of the firmware might be different. Menus and processing on MIPS-based computers and PPC-based computers are similar.

When you start an Alpha-based computer, you see the Boot menu, which looks like this:

ARC Multiboot Alpha AXP Version 3.5-11
Copyright (c) 1993 Digital Equipment Corporation

Boot Windows NT Workstation Version 4.0
Boot an alternate operating system
Run a program

Use the arrow keys to select, then press Enter.


The first two selections are described in the section titled "Boot Menu (RISC-based Computers)," presented earlier in this chapter. Information about those selections is not repeated here.

For more information about ARC path names, which are used in boot selections, see Chapter 20, "Preparing for and Performing Recovery."

#### Selecting Run a Program

When you select Run a program, you see the following screen:

ARC Multiboot Alpha AXP Version 3.5-11
Copyright (c) 1993 Digital Equipment Corporation

Program to run:


From this prompt, you can start any program that has been compiled for an Alpha-based computer. You must know the complete ARC path to the program, unless the NVRAM has the correct environment variables defined for devices. For example, if there are environment variables for the cd-rom drive (CD:) or the floppy disk (A:), you can use them instead.

For example, to start Windows NT Setup, where the CD is a default device on the computer, you can type the following:

Program to run: CD:\alpha\setupldr


When running a program stored on the hard disk, you must use the full ARC pathname and filename, such as the following:

Program to run: scsi(0)disk(0)rdisk()partition(1)\alpha\setupldr


If you try to use the MS-DOS syntax to run a program on the hard disk, you get an error message like the following:

Program to run: C:\alpha\setupldr

Pathname is not defined
Press any key to continue...


Note The firmware routines can access only FAT partitions or CD-ROM drives. They cannot access NTFS partitions.

##### Running Arcinst

Arcinst.exe is an AXP native mode application program (requires no operating system) that performs the same functions as the MS-DOS-based utilities Fdisk and Format. You can use Arcinst to define and automatically format partitions. This application program is on the Windows NT product CD.

To start Arcinst, type in the following at the Program to run prompt:

Program to run: cd:\alpha\arcinst


When the program starts, it displays the following menu:

Arc Installation Program Version 4.00

Configure Partitions
Exit

###### Configure Partitions

If you select Configure Partitions, you see the following menu:

Arc Installation Program Version 4.00

Create Partition
Delete Partition
Make Existing Partition into System Partition
Exit

Create Partition

Arcinst creates the first two partitions on a hard disk as physical partitions. The second partition is always an extended partition; any additional partitions are defined as logical drives within the extended partition. There are no user-defineable parameters for these options. Drive letters are not assigned, since the ARC specification for path names does not include them.

After creating any partition, the system automatically formats it as FAT. There is no option to skip formatting the new partition. This is a sample of the information you see when you select Create Partition:

Arc Installation Program Version 4.00

Scsi bus 0, Identifier 3, Disk 0 (scsi(0)disk(3)rdisk(0))
Scsi bus 0, Identifier 0, Disk 0 (scsi(0)disk(0)rdisk(0))


When you select one of the disks, you see the following screen:

Enter size in MB (1-191):


The available size is the unpartitioned disk space remaining on the disk. When you enter the size, you see messages such as the following:

Partition successfully created.
Press any key to continue....

Formatting scsi(0)disk(0)rdisk(0)partition(3)
99 percent formatted


If the disk that you select has no unpartitioned area, you see the following message:

Disk is full
Press any key to continue...

Delete Partition

You can delete any partition or logical drive, in any order. When you delete a volume, any data on that volume is no longer accessible. When you select Delete Partition, you see information such as this:

Arc Installation Program Version 4.00

Scsi bus 0, Identifier 3, Disk 0 (scsi(0)disk(3)rdisk(0))
Scsi bus 0, Identifier 0, Disk 0 (scsi(0)disk(0)rdisk(0))


When you select one of the disks, you see a screen similar to this one:

1010 MB Fat Partition


Select a volume to delete. If the partition is the system partition, you get an error message like:

The selected partition is (or contains) a system partition
Are you sure you want to delete it (y/n)?


If the partition is not the system partition, you see a screen similar to:

509 MB Extended Partition also results in the deletion of:
509 MB HPFS/NTFS Logical Volume
Are you sure you want to delete it (y/n)?


When you enter y to either of these preceding questions, you see the following screen:

Partition deleted successfully.
Press any key to continue.


Make Existing Partition into System Partition

When you select this option, you see a screen similar to the following:

Arc Installation Program Version 4.00

Scsi bus 0, Identifier 3, Disk 0 (scsi(0)disk(3)rdisk(0))
Scsi bus 0, Identifier 0, Disk 0 (scsi(0)disk(0)rdisk(0))


If the partition you select is already the system partition, you see the following screen:

Partition is already a system partition.
Press any key to continue...


Otherwise, you see information like the following:

Partition 2 (200 MB HPFS/NTFS)


The system partition must be formatted as FAT. Selecting an NTFS partition results in this message:

System partitions must be formatted with the FAT filesystem.
Do you wish to format the chosen partition (y/n)?


When you enter y, this message is displayed:

All existing data will be lost. Are you sure (y/n)?


Entering y causes the partition to be formatted as FAT.

99% complete
Press any key to continue...


##### Running the Repair Procedure

If your system files or Partition Boot Sector are corrupt, and you are unable to restart by using the Last Known Good Configuration, you can use the Repair process in Windows NT Setup to repair your system.

To repair a Windows NT installation, you need the configuration information on \%systemroot%\Repair or the Emergency Repair Disk that you created when you installed Windows NT (or you created later by using the Repair Disk utility).

To start the Windows NT Setup program from the CD-ROM, select Run a program from the Boot menu and enter the following at the prompt:

Program to run: CD:\alpha\setupldr


Once setupldr starts, the procedures are the same as for an x86-based computer.

When you select the Supplementary menu option from the Boot menu, the firmware displays this screen:

ARC Multiboot Alpha AXP Version 3.5-11

Install new firmware
Install Windows NT from CD-ROM
Set up the system...
Display hardware configuration

Use the arrow keys to select, then press Enter.

##### Install New Firmware

Installing new firmware results in the following:

• All NVRAM settings, such as boot paths, definitions for CD: and A:, environment variables, and the default configuration, are deleted.

• EISA configuration information is cleared.

If you want to save the information that is currently in the NVRAM, you can use the saveenv and restenv utilities, which are available from Digital Equipment Corporation. Run these utilities from the Run a program menu to save your current NVRAM settings to a file on the disk, and then restore them.

###### To upgrade the firmware without wiping out all settings.
1. Put the disk with the utilities in the floppy drive.

2. On the Boot menu, click Run a program, and enter a:\saveenv. You see the following message:

This saves the environment variables into the floppy
file fwenv.sav. Continue (Y,N)?


When you click Y, you see these messages:

Opening eisa()disk()fdisk()fwenv.sav.
Saving the firmware environment variables.
Environment successfully saved! To restore them,
run the Restenv program.

Press any key to continue.

3. On the Supplementary menu, click Install new firmware, and follow these steps:

Searching floppy and CD-ROM for the firmware update tool...


If the tool cannot be found or is corrupt, this message is displayed:

Error: Bad device name/number or partition number, press any key to continue


If the firmware files are found, messages like these are displayed:

DECpc AXP 150 Flashfile Update Utility, revision 2.09

This will update your machine's firmware.

Press the "Y" key to continue with the update.
Hit any other key to abort.


After selecting Y, you have choices such as the following:

Select location of update file.

Use the arrow keys to select, then press Enter.
Hit Escape to abort.

Floppy #0\jensfw.bin
CD-ROM\jensfw.bin
Other location
Exit


Select the floppy disk or CD-ROM, depending on the location of the firmware files. When you press ENTER, you should see:

Loading the update file...


followed by:

The update file is good!
The name of the firmware update is...:


The name depends on the firmware version.

Press the "Y" key to continue the update.
Hit any other key to abort.


When you select Y, you see:

Are you *really* sure?
Press the "Y" key to continue the update.
Hit any other key to abort.


When you select Y again, you should see information similar to:

Firmware ROM type: 0.
Updating these blocks:
7 8 9 10 11

The update has succeeded. Power-cycle the machine to see the changes.

Press any key to continue...


The blocks that are updated depend on the firmware version being updated.

4. Do not restart the computer yet. On the Supplementary menu, click Run a program, and enter a:\restenv. You see the following messages:

Restenv version 4.31

This restores the environment variables from floppy
file fwenv.sav. Continue(Y,N)?


Enter Y, and you see the following messages:

Opening eisa()disk()fdisk()fwenv.sav.
Checking fwenv.sav type bye.

The environment variables have been restored

Press any key to continue


Press any key.

5. Restart your computer. You will get some error messages about the EISA configuration being out of date, which you can ignore for now.

6. Put the floppy disk with EISA configuration utility in the floppy drive.

7. On the Supplementary menu, click Set up the system.

8. On the Setup menu, click Run EISA configuration utility from floppy. All you should need to do when running this utility is press ENTER until you return to the Setup menu. The Setup menu is described later in this chapter.

10. Restart the computer again. You should now be running with the new firmware.

##### Install Windows NT from CD-ROM

When you select Install Windows NT from CD-ROM, the firmware displays the message:

Loading Microsoft Windows NT Setup. . .


The next screen is the standard Windows NT Setup screen. The rest of the installation is identical to installing Windows NT on an X86-based computer.

You can also run the Repair procedure by selecting this option. When Windows NT Setup displays the Welcome to Setup screen, select R for repair. The rest of the repair procedure is identical to what happens on an x86-based computer.

##### Set Up the System (Setup Menu)

Selecting Set up the system takes you to the Setup menu, which enables you to change the configuration options for all operating systems, and the computer configurations options stored in the NVRAM. You can change the following types of information:

• Environment variables.

The following example shows the Setup menu. If you make changes to the computer configuration by making selections from the Setup menu, the additional selection:

Supplementary Menu, and save changes...


appears as the last line of the menu. Changes are not actually saved to the NVRAM until you make this selection. This example includes the additional line.

ARC Multiboot Alpha AXP Version 3.5-11 Tuesday, 2-20-96 2:53:19 PM
Copyright (c) 1993 Digital Equipment Corporation

Set system time
Set default environment variables
Set default configuration
Setup autoboot
Machine specific setup...

Edit environment variables
Reset system to factory defaults

Help
Supplementary menu, and do not save changes...

Use the arrow keys to select, then press Enter.


If any of the changes that you make by using the Setup menu result in inconsistent information in the NVRAM, the selection with the error is in yellow text. And the following message is displayed at the bottom of the screen, also in yellow text:

The yellow items should be done before booting Windows NT


Note The Setup menu on other versions of the Alpha-based computer firmware might have different entries. For example, you might have the entry Run EISA configuration utility from floppy.

###### Set System Time

To set the system date and time, select Set system time from the Setup menu. You can enter the following information:

Tuesday, 2-20-1996 3:03:48 PM

Enter the new date (mm-dd-yy) :
Enter time (hh:mm:ss) :


When setting the time, you must enter the time in 24-hour format. For example, the time listed above should be entered as 15:03:48.

###### Set Default Environment Variables

To set the defaults for booting, select Set default environment variables on the Setup menu. This example shows the user selecting the SCSI Hard Disk as the location of the default system partition.

Tuesday, 2-20-1996 3:08:48 PM

Enter location of default system partition:

Select media:
SCSI Hard Disk
Floppy Disk
CD-ROM

Enter SCSI bus number: 0
Enter SCSI ID: 0
Enter partition (must be FAT or NTFS): 1

###### Set Default Configuration

To set the default configuration, select Set default configuration on the Setup menu. The available selections depend upon your computer hardware.

Tuesday, 2-20-1996 3:09:28 PM

Select monitor resolution:
1280x1024
1024x768
800x600
640x480

Select floppy drive capacity:
5.25" 1.2MB
3.5" 1.44MB
3.5" 2.88MB

Is there a second floppy:
Yes
No

Select keyboard:
U.S. 101-key keyboard
Japanese 106-key keyboard
French 102-key keyboard
German 102-key keyboard
Spanish 102-key keyboard
Spanish variation
Swiss 102-key keyboard
Italian 102-key keyboard
Finnish/Swedish keyboard
Norwegian keyboard
Danish 102-key keyboard

Enter SCSI Host ID (0-7) for SCSI bus number :


After selecting the setting in each group, you are returned to the Setup menu.

When you select Manage boot selections menu on the Setup menu, you can configure and manage the operating systems that appear on the Boot menu at startup. You can also configure custom startup folders and files if you have installed multiple copies of Windows NT.

The following choices are available on the Boot selections menu:

Tuesday, 2-20-96 2:59:19 PM

ARC Multiboot Alpha AXP Version 3.5-11
Copyright (c) 1993 Digital Equipment Corporation

Change a boot selection
Check boot selections
Delete a boot selection
Dump boot selections
Rearrange boot selections

Use the arrow keys to select, then press Enter.


• You have installed another operating system or more than one instance of Windows NT.

• You have configured your system partition or boot partition as a mirror set (Windows NT Server only).

• You want to create a boot selection for your Windows NT startup floppy disk. See Chapter 20, "Preparing for and Performing Recovery," for information about the Windows NT startup floppy disk.

When you make this selection, you can enter information similar to the following:

Note The right justified arrows (<----) in these examples indicate which selection was made, or the information that was entered.

Tuesday, 2-20-96 3:09:19 PM

Select a system partition for this boot selection:
SCSI Bus 0 Hard Disk 0 Partition 1
New system partition

Enter location of system partition for this boot selection:
Select Media:
SCSI Hard Disk <---------------------------------------------------
Floppy Disk
CD-ROM

Enter SCSI bus number: 0 <---------------------
Enter SCSI ID: 2 <---------------------
Enter Partition (must be FAT or NTFS): 1 <---------------------

Is the operating system in the same partition as the osloader:
Yes
No <----------------------------------------------------------------

Enter the location of os partition:
Select Media:
SCSI Hard Disk <---------------------------------------------------
Floppy Disk
CD-ROM

Enter SCSI bus number: 0 <-------------------------------------
Enter SCSI ID: 2 <-------------------------------------
Enter Partition: 2 <-------------------------------------

Enter the operating system root folder: \winnt <--------------
Enter a name for this boot selection: Boot Shadow Disk <--------------

Do want to initialize the debugger at boot time:
Yes
No <----------------------------------------------------

Change a Boot Selection

When you select Change a boot selection on the Boot selections menu, you can change environment variables for any of the boot selections that you have defined. This is a sample screen:

Tuesday, 2-20-96 3:15:09 PM
Selection to edit:
Boot Windows NT Workstation 4.0 (Default)
Boot Windows NT Workstation 3.51


When you select one of the entries, you see a screen like this one:

Tuesday, 2-20-96 3:17:19 PM

Use arrow keys to select a variable, ESC to exit:

Name:

Environment variables for boot selection 1:
LOADIDENTIFIER= Boot Windows NT Workstation 4.0
SYSTEMPARTITION=scsi(0)disk(0)rdisk()partition(1)


Use the arrow keys to select the environment variable to edit and press ENTER. The screen changes to have the heading Value: under Name:. For instance, if you select OSLOADOPTIONS and press ENTER, you see the following:

Name: OSLOADOPTIONS
Value: nodebug


Edit the value, and press ENTER when done. Press the ESCAPE key to exit this menu and return to the Boot selections menu.

Check Boot Selections

Under normal circumstances, when you select Check boot selections on the Boot selections menu, the screen briefly displays the various startup selections as they are checked for validity. If there is a problem, such as an invalid path or file, the following information is displayed:

Tuesday, 2-20-96 3:25:11 PM

Problems were found with Windows NT Workstation 4.0... Choose an action:

Ignore problems with this boot selection
Delete this boot selection
Change this boot selection

The error is displayed in yellow text below the options, such as the following:

OSLOADER cannot be found, value is:


The firmware only checks that the paths are valid and that the files or folders exist. It does not check file sizes, version numbers, dates, switches, or any other fields that might indicate consistency problems.

The firmware automatically returns you to the Boot selections menu.

Delete a Boot Selection

If you have deleted a Windows NT installation from your computer, you should select Delete a boot selection on the Boot selections menu to remove it from the NVRAM. This is the screen you see when you select this option:

Tuesday, 2-20-96 3:25:09 PM

Selection to delete:
Boot Windows NT Workstation 4.0 (Default)
Boot Windows NT Workstation 3.51


Use the arrow keys to highlight the selection you want to delete, and press ENTER. There are no warnings or checks, and the selection is immediately deleted. Changes are not saved to NVRAM until you exit the Setup menu, however.

Dump Boot Selections

When you select Dump boot selections on the Boot selections menu, the NVRAM resets to no boot selections.

This is a sample screen:

LOADIDENTIFIER= Boot Windows NT Workstation 4.0;Boot Windows NT Workstation 3.51
SYSTEMPARTITION=scsi(0)disk(0)rdisk(0)partition(1);
scsi(0)disk(0)rdisk(0)partition(2);
scsi(0)disk(0)rdisk(0)partition(2);

Press any key to continue...


Changes are not saved until you exit the Setup menu, and select Supplementary Menu, and save changes. If you save changes when exiting, the only ways to restore boot selections are to manually reenter the information or use the Emergency Repair disk.

Rearrange Boot Selections

The most common reason for rearranging the boot selections is because you have added a boot selection, which is automatically placed at the top of the list.

You see a screen like this one when you select Rearrange boot selections on the Boot selections menu:

Tuesday, 2-20-96 4:01:03 PM

Pick selection to move to the top, ESC to exit:
Boot Windows NT Workstation 4.0 (Default)
Boot Windows NT Workstation 3.51


Use the arrow keys to highlight the selection you want to move to the top of the list, then press ENTER. You can do this repeatedly to rearrange the boot selection into any order you want.

As before, changes are not saved until you exit the Setup menu, and select Supplementary Menu, and save changes.

###### Setup Autoboot

The Setup autoboot selection on the Setup menu enables you to set your computer to automatically start the default selection if you do not make a selection from the Boot Loader menu.

You see a screen like this one when you select this option on the Setup menu:

Wednesday 2-21-1996 8:01:36 AM

Should the system autoboot:
Yes
No

Enter Countdown value (in seconds): 30


The Enter Countdown value prompt appears only if you select Yes. The countdown value provides the same functionality as the timeout value in the Boot.ini file on an x86-based computer.

###### Machine Specific Setup

When you select Machine specific setup on the Setup menu, you can set environment variables that are specific to the computer, such as:

Wednesday 2-21-1996 11:01:36 AM

PCI Parity checking currently set to: Off

Set PCI Parity checking currently set to: On


Selecting one of the options sets the environment variable to the value specified. Selecting Setup menu returns you to that menu.

###### Edit Environment Variables

You can add, delete, or change information for the environment variables by selecting Edit environment variables on the Setup menu. The screen displays the variables that are defined, and their values, such as this example:

Wednesday 2-21-1996 8:09:16 AM

Use the arrow keys to select a variable, ESC to exit:

Name:

Environment variables:
CONSOLEIN=multi()key()keyboard()console()
CONSOLEOUT=multi()video()monitor()console()
FWSEARCHPATH=scsi(0)disk(0)rdisk()partition(1)
A:=multi(0)disk(0)fdisk(0)
FLOPPY=2
FLOPPY2=N
KEYBOARDTYPE=0
TIMEZONE=PST8PDT


You can add environment variables by typing in the name of the new variable at the Name: prompt and pressing ENTER. A prompt for Value: appears beneath the Name: prompt, and you enter the value.

For instance, to add the countdown variable:

Name:COUNTDOWN
Value: 20


To delete an environment variable, select it with the arrow keys, or type in the name at the Name: prompt. Then press ENTER at the Value: prompt. Environment variables with no string value are deleted from the NVRAM.

###### Reset System To Factory Defaults

Be careful when you select this option. When you execute this command, you might no longer be able to start the computer. Some reasons for the failure are:

• Windows NT might not have been pre-installed, so you would delete all references to Windows NT and all its environment variables.

• Windows NT could be on a different partition or folder than the factory default, so the path to Windows NT would not be correct.

• If you have changed hardware on the computer, you would get information only for the initial configuration.

Before you execute the command, write down all configuration information that you need to know, such as:

• Which partitions are defined.

• Which partitions are the system and boot partition.

• The environment variables for each boot selection, especially the paths to the boot selection.

This is a sample screen:

Wednesday 2-21-1996 8:15:16 AM

This command will overwrite the environment, configuration,
and boot selections with new information.

Are you sure you want to do this?
Yes
No


Selecting Yes causes the default configuration information to be saved to NVRAM. Once you do this, there is no way to recover any previous configuration information. You have to rebuild all custom options and configuration parameters by using the firmware menus.

###### Help

This selection displays the system help screen.

Wednesday 2-21-1996 8:26:11 AM

Do the following steps, in this order, to set up the system:

1. Set system time.
2. Set default environment variables.
3. Set default configuration.
4. Create at least one boot selection.
5. Setup autoboot.

-> A menu item with an arrow represents a section of the NVRAM with a
problem. Select these items (in top to bottom order) to repair the
NVRAM before attempting to boot or install Windows NT.

"Reset system to factory defaults" does steps 2--5 for a typical system.

The ESCape key returns from a menu and aborts a sequence.

The firmware automatically reboots if the configuration is changed.

Press any key to continue...


If you have made changes to the NVRAM by using the Setup menu, there are two ways to exit to the Supplementary menu:

Supplementary menu, and do not save changes...


If you choose to save the changes, they are saved to NVRAM. If you did not make any changes, the second option does not appear on the screen.

##### Display Hardware Configuration

• Firmware.

• Processor.

• Video.

• Current environment variables for all devices on the system.

• EISA slots.

This is an example:

Friday 2-23-1996 10:46:15 AM
Devices detected and supported by the firmware:

multi(0)video(0)monitor(0)
multi(0)key(0)keyboard(0)
multi(0)disk(0)fdisk(0)
multi(0)serial(0)
multi(0)serial(1)
scsi(0)disk(0)rdisk(0)
scsi(0)cdrom(4)fdisk(0)

Press any key to continue...


Selecting any key displays a list of supported hardware, such as the following:

Friday 2-23-1996 10:46:55 AM
Alpha AXP Processor and System Information:

Processor ID 21066
Processor Revision 2
System Revision 1
Processor Speed 166.66Mhz
Physical Memory 32 MB
Backup Cache Size 256 KB

Press any key to continue...


When you press any key, the firmware displays the next set of information. When all hardware information has been displayed, selecting any key returns you to the Supplementary menu.