Windows NT 4.0 Chinese version of the boot process
● Text / Lai Rong
Understanding the power system's power-on process is the knowledge necessary for people who want to in-depth operation system. Windows NT itself supports multiple boot. The complexity of the power-on process is no longer the previous DOS.
When you open the computer power of the Windows NT 4.0 Workstation, your computer starts to load the Windows NT system, although the light is displayed on the screen of the computer screen, it does not feel the complex of Windows NT booting, but as long as you Slightly compare Windows 95 with WindowsNT boot time, you will definitely find that Windows NT's boot action is indeed more complicated.
For Windows NT, starting from your computer power supply, until you have to press Ctrl, Alt, and Del Buttons on the screen, all the processes of Windows NT are the power-on process of Windows NT, in which during this process, The power of Windows NT is responsible for loading the entire system into the memory. For readers who want to know the core of the Windows NT system, they must first understand the loading situation of the entire system, so in this period of the article about Windows NT 4.0 Workstation, let us discuss Windows NT 4.0 Workstation. The boot process.
From the start of the computer power, the process of logging in to the conversation window on the screen is all on the power-on process of Windows NT. Of course, the power-on process of any operating system is nothing more than the memory of the system from the disk or BIOS, and performs, then initialize the entire system, then wait for the user's operation; Windows NT Also, let us now come to the power-on process of Windows NT.
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From the start of the computer power, the process of logging in to the conversation window on the screen is all on the power-on process of Windows NT. Of course, the power-on process of any operating system is nothing more than the memory of the system from the disk or BIOS, and performs, then initialize the entire system, then wait for the user's operation; Windows NT Also, let us now come to the power-on process of Windows NT.
I often assemble it. The readers who have repaired the computer may have some small questions in the computer POST. About the problem of this area, you can refer to the manual attached to the motherboard or the computer DIY book between the reference square.
MBR loads into the PBS of Active Partition
After completing the action of the POST, the BIOS will read according to the setting on the CMOS, to the 0th track of the power-on disk (usually the hard disk), and execute the program inside MBR (Master Boot Record). The role of MBR is to read the Active Partition set in the disk segmentation table (partition table), which is more accurate, MBR reads, executes the content of Active Part 0 magnetic zone (Sector 0), this magnetic area said For the Partition Boot Sector, in the PBS, a section can be used to load the operating system, which is placed by the job system when installing a job system. Because MBR starts the execution of PBS, the entire computer is now going to enter the operation system. Of course, if MBR can't find Active Partition, then MBR will display an error message like Missing Operating System, etc. on the screen, so if your Windows NT does not open normally, and you see a mistake similar to this on the screen. The message is mostly the disk division table of the hard disk.
OS Loader loaded with Windows NT
PBS is a program provided by the job system. Its purpose is to load the operating system, and the Windows NT boot file loaded by PBS is NTLDR, you can find the first hard disk root directory of the Windows NT computer. This file, and NTLDR can only be placed here, otherwise Windows NT will not be able to start. Because NTLDR is a system file, you must adjust the archive check options for the archive of the file, or add / a parameter to the DIS window to add / a parameters to find this file. NTLDR shoulder the responsibility of the Windows NT job system, the entire Windows NT system's load process is dominated by it. However, in addition to NTLDR, some files must also be in the root directory of the first hard disk: * NTDetect.com is used when Windows NT is turned on, and the programs around the hardware are used.
* bootfont.bin provides Chinese characters when Windows NT Chinese.
* Boot.ini This is a Text text file that records the option content when Windows NT.
* Bootsect.dos Its content is a Windows 95 or DOS version of PBS, if you use NT OS Loader to make multiple boots with Windows NT, then this file must also be available.
* Ntbootdd.sys If you have the hard disk of the SCSI interface, you must also have this driver.
Multiple boot options
When NTLDR begins to execute, you will see the multi-power option screen of Figure 1 on the screen, and the multi-power option is NTLDR to determine the content of Boot.ini, and boot.ini is a text file, so you can Modify the content of Boot.ini to change the multi-power option. Previously mentioned bootsect.dos, the content of this file is the Windows 95 / DOS version of PBS. If you use OS Loader Multi-power option to select Windows 95 or DOS to be powered on, then NTLDR will load BootSect. DOS content and transfer control to it, then, your computer will boot in Windows 95 or DOS.
Detecting hardware peripheral equipment
If you are using Windows NT as a boot job system in a multi-power option, then NTDECT.com will also perform NTDetect.com to detect computer hardware peripherals, and NTDetect.com will pass the computer hardware detection results back to NTLDR, at this time, "NTDECT V1.0 is checking hardware ...".
Select hardware setting file
Next, NTLDR will display a paragraph on the screen, prompting you to replace the hardware setting file, if you press the blank key, NTLDR will have a screen that allows you to choose the hardware setting file; but if you There is no blank key, and NTLDR will load the preset hardware setting file.
Or you can press the blank key first, then enter the screen that selects the hardware setting file to select the hardware settings that can be smoothly turned on, sometimes you may need this feature to launch Windows NT smoothly.
You can use the mouse button dual to press the system illustration in the console, and then proceed with the hardware setting page of the system content conversation window to handle the setting of the hardware setting file. As shown in Figure 2, you can copy, delete hardware settings, or change the content or name of the change hardware setting file, and adjust the time of NTLDR Wait for the user to select the hardware setting file.
Load system core
Next, NTLDR will load the core of Windows NT, at this time, NTLDR will load the Windows NT core file, which is ntoskrnl.exe, and Hal.dll (Hardware Adaptation Layer) You will in the black On the screen, I saw a lot of points (.) On the screen, then NTLDR will read the contents of the login system hkey_local_machine / system.
When Windows NT will turn on the job system, all the hardware-related data is put in hkey_local_machine / system / controlsetxxx, as shown in page Figure 3, this is the Windows NT login system information of my computer, you can find that there is contral set001, controlset002, etc. Two ControlSetxxx machine code. However, which machine code is loaded when the Windows NT system is turned on? The key is the content of the Default value of the SELECT code. As the right pane of Figure 3, the Default value of the SELECT code is 1, which means that the information in the HKEY_LOCAL_MACHINE / SYSTEM / ControlSet001 will be used as the hardware preset information when the Windows NT system is turned on, if you have The hardware setting file / setting restore function table selects other hardware settings files, then NTLDR will load the CONTROLSET included in the hardware setting file.
Moreover, NTLDR will record the CONTROLSET number used in the boot to the CURRENT value of the SELECT code. For example, the power-on is the content of the hardware setting file with the hardware data of the controlset001, then the Current value of the SELECT code code is Will be 1. However, NTLDR does not directly use the information recorded in HKEY_LOCAL_MACHINE / System / ControlSetxxx, but the data is copied to the HKEY_LOCAL_MACHINE / System / CurrentControlSet machine code.
There is a Services subroutine code under hkey_local_machine / system / currentcontrolset, and every subcam code under Service is a service item that the Windows NT system should be loaded when booting. At this time, NTLDR will check HKEY_LOCAL_MACHINE / System / CURRENTCONTROLSET / Service At the end of the START value of each service item subcam, if the start value is 0, NTLDR will load the driver of the service item at this time. At this time, NTLDR is under the state of the CPU for Real Mode, using the BIOS INT 13 system call to load these drivers; if your hard disk is the SCSI interface, then ntbootdd.sys will be able to send it up. Used to load these drivers.
System core initialization
Next, Windows NT's boot process is about to enter the system core initialization. When the core of the Windows NT system begins to enter initialization, the main power of the system has been transferred from NTLDR to ntoskrnl.exe, and the entire screen will present a blue picture. And display the version of Windows NT, Build serial number, and the number of CPUs and memory configured on your computer. Ntoskrnl.exe first establishes a hkey_local_machine / hardware code according to the data given by NTLDR (actually detected by NTDetect.com, and then transmitting it to NTLDR), which means that this code will be turned on. Updated by re-detection by NTDETECT.COM.
Next, ntoskrnl.exe will check the START value of each service item subcipe under HKEY_LOCAL_MACHINE / SERVICE, if the stat value content is 1, then NTLDR will load the service item at this time. Driver.
The role of session manager (smss.exe) is to load these START value content 1 service, and in this time NTLDR will check HKEY_LOCAL_MACHINE / SYSTEM / CU RRENTCONTROLSET / CONTROL / SESSIONMANAGER Code will have sufficient information. SESSION MA Nager.
The login system then, Windows NT will enter the GUI screen, and start Winlogon.exe by ntoskrnl.exe to prepare for the user to log in, Winlogon.exe will start a program called Local Security Administration, LSAss.exe, LSAss.exe will be responsible for displaying login conversation window, etc. Let the user enter the user name, password action. The Windows NT at this time may be in progress, such as the work initialized by the network-related driver, but you can still log in.
Then Service Control (Screg.exe) also checks the content of the START value of each service item subcode under the HKEY_LOCAL_MACHINE / SYSTEM / CU RRENTCONTROLSET / Service, if the start value is 2, then scheve.exe will Load the driver of the service item at this time. So far, Windows NT finally completes the entire power-on action, and the user is also logged in to the Windows NT system and starts operating Windows NT. Figure 3 shows the code information in the login editor
in conclusion
Understanding the operating system is an essential knowledge that wants to in-depth operation system core, for Windows NT, this huge job system, its boot process is not single, because Windows NT itself supports multiple boot Therefore, the boot process is more complicated. From MBR, PBS, NTLDR, to Ntoskrnl.exe load, initially numerous service items, to finalize WinLogon.exe allows users to log in, the complexity of the Windows NT boot process is no longer the previous DOS.
Understanding the operating system starts from the start of the operating system, and from this article, you should also find that the information in the login system is quite important for Windows NT's boot process, but the information on the login system is not only important for booting, it It can be said that the soul of the entire Windows NT job system. If there is a chance, I will talk to the reader about the topic of the Windows NT login system.
START value content
HKEY_LOCAL_MACHINE / SYSTEM / CURRENTCAL_MACHINE / SYSTEM / CURRENTCONTROLSET / SESTEM / CURRENTCONTROLSET / Service At the bottom of each service item, there is a start value, which is different in accordance with the status of each service item. From the above-mentioned Windows NT, you will find that when NTLDR loads the system core, load the service item driver of the start value of zero together; when the system enters the initial phase, NtoskRNL.exe will load Start. The value of the value of 1 is 1 service; and when the user logs into the system, the Session Manager will load the START value of 2 service item drivers.
The original START value is recorded by the service project driver, when it is loaded, the STARS is currently five states such as 0, 1, 2, 3, 4, 0, 1, 2 represent Boot, respectively. , SYSTEM, Auto Load, etc. The service item representative of the START value is 3 let the user load (Load On Demand) in manual mode, and 4 means the state of deactivation, that is, not load.
You can use the service diagram of the console, then press the service conversation window of the service conversation window, you can use the service conversation window (Figure 4) that appears (Figure 4) to adjust the startup value of the service item, where Automatic, manual, and deactivation of the service conversation window is 2, 3, 4, etc.
