China DOS Union

### Problem Presentation
To ensure computer security or speed up system startup, it is generally set in the BIOS to prioritize booting the system from the hard disk. However, once a situation arises where a bootable disk is needed to boot the system (such as completely eliminating viruses under DOS, upgrading the BIOS, etc.), one has to first enter the BIOS to make modifications, and after completing the task, one has to enter the BIOS again to change the relevant settings back, which is very cumbersome. Is there really no way to have the best of both worlds? After continuous exploration and experimentation, a solution that achieves both has finally been found.

### Idea for Solving the Problem
Friends who have installed dual systems of Win98 and Win2000/XP know that there is a boot configuration file boot.ini of the boot manager in the root directory of drive C. In the section of this file, there is a line: C: \= "Microsoft Windows", which is a default usage. Its complete usage is: C: \BOOTSECT.DOS = "Microsoft Windows", where BOOTSECT.DOS is the boot sector file of Win98, hidden in the root directory of drive C, and "Microsoft Windows" in quotes is the menu item to boot Win98. The function of this line is: when selecting "Microsoft Windows" from the "boot menu", the boot manager boots Win98 from the BOOTSECT.DOS file. From the process of booting Win98 from the dual operating system, the following conclusion can be drawn: if the boot sector of the bootable disk is extracted and made into a file saved in the root directory of drive C, and the relevant statements in the boot.ini file are modified accordingly, it is possible to boot the system from the bootable disk from the "boot menu", thus avoiding modifying the BIOS.

### Implementation Steps
1. **Install the boot manager of Win2000/XP**
The boot manager has been installed in Win2000/XP or in the dual system of Win98 and Win2000/XP. The following introduces the process of installing the boot manager in Win98.
Run the installation program on the Win2000/XP installation CD in Win98, select "Clean Installation", and keep installing until the boot menu appears with "Microsoft Windows" and "Microsoft Windows 2000/XP Installation Program" when booting. At this time, the boot manager of Win2000/XP has been installed. Select "Microsoft Windows" to enter Win98 and delete all files starting with $ and ending with $ in all partitions of the hard disk.
2. **Make the boot sector file of the bootable disk**
The following introduces the method of using the DEBUG tool built in the Win98/2000/XP system to make the boot sector file of the bootable disk.
First, insert the bootable disk into the floppy drive, then enter DEBUG and press Enter at the command prompt of Win98/2000/XP, and then enter the following commands in sequence and press Enter under the DEBUG prompt "-":
-L 100 0 0 1
-RCX
:200
-N C:\FBOOT.DOS
-W
-Q
Explanation: The first line of the command is to read the boot sector of the bootable disk into the memory. The second and third lines of the command are to set the size of the boot sector file to 200B (200B is in hexadecimal, that is, 512B in decimal). The fourth line of the command is to name the boot sector file as FBOOT.DOS. Readers can name it according to their own preferences. The fifth line of the command is to write the data in the boot sector in the memory into the FBOOT.DOS file. After the writing is completed, the screen will display "write 00200 bytes" (the size of the written file is 200B), indicating that your boot sector file has been successfully made. Enter the sixth line of the command Q to exit DEBUG.
3. **Modify boot.ini**
Modify the boot.ini file in the Win98 system as follows:

timeout=0
default=c:\

C:\= "Microsoft Windows"
C:\FBOOT.DOS= "Boot the system from the bootable disk"
In the Win2000/XP system, add C:\FBOOT.DOS= "Boot from the bootable disk" under the section, and modify the value of timeout to 0.

### Boot the System from the Bootable Disk
After completing the above operations, restart the computer. If you need to boot the system from the bootable disk at this time, press F8 to enter the "Windows Advanced Options Menu", select "Return to the Operating System Options Menu", press the Enter key to enter the "Boot Menu", insert the bootable disk into the floppy drive, and then select "Boot the system from the bootable disk" to boot the system from the bootable disk. If you do not need to boot the system from the bootable disk, you can quickly boot your Win98/2000/XP system without any operation.

Virtual Floppy by lyh728
http://bbs.wwwfox.net/non-cgi/usr/2/2_10625.rar

This is a virtual floppy system similar to PQMagic's vfloppy.sys that I implemented by referring to the source code of GRUB and the disassembled code of PQMagic's vfloppy.sys.
See brother vx_xsj's post at the end.
Why do I need to modify it when there is PQMagic's vfloppy.sys?
Mainly, the boot program of PQMagic's vfloppy.sys is placed in the MBR and occupies the first 3 sectors of the disk. That is to say, when installing vfloppy.sys, it needs to write data to the first 3 sectors starting from the MBR. So if an error occurs at this time, the system may be unable to boot.
Then is there any other boot program that can do similar work?
LILO needs to be installed under Linux and cannot virtualize floppies.
nu2.nu's diskemu is on the CD and does not support FAT, NTFS.
BootScriptor is also on the CD and does not support FAT, NTFS.
Isolinux is also on the CD and does not support FAT, NTFS.
SYSLINUX can support FAT16, FAT12 but not FAT32, NTFS.
GRUB supports the most formats. Some people are working in this direction, but it is not easy to use at present (referring to virtualizing floppies on the hard disk), and it is most likely to achieve this goal in the near future.
............
So I combined the source code of GRUB and the binary file of vfloppy.sys to make this thing.
Usage:
Suppose vfloppy is placed in c:\boot, and the C drive can be in FAT16, FAT32, NTFS partition format.
Run vfloppy -1 vloader.bin -2 vmemdsk.bin -i dos.img,

Add a line in c:\boot.ini: c:\boot\vloader.bin ="virtual floopy "
After restarting the system, select "virtual floopy" in the NTLoader menu.
It will load the c:\boot\dos.img image and run it.
Features:
Safe, does not write code to the boot sector, will not damage the system, no need to restore the MBR.
Convenient, can restart the system at any time and enter the DOS environment.
Very convenient to run other OS on systems without CD-ROM drives, without floppy disks, only Windows NT, Windows 2k, Windows XP, Win2k3.

Testing:
Tested and passed in the English Standard Edition of Win2k3, supports NTFS, FAT32, FAT16 partitions.
MS DOS7.10 boot disk made by DOS Forum moderator Wengier

Reference:
calV's question:

My CD-ROM drive and floppy drive are broken, but I want to reinstall 2000 under DOS. Is there any way? Help, whatever it is. Can I delete some 2000 system files so that it can't enter 2000 when booting and directly jump to the DOS mode?

Brother vx_xsj's post:
_________ vx_xsj's Release Announcement! ! ! ! _________

　　calV's question I have helped him solve. I said it can be done, naturally it can be done, because I don't lie, so this is
possible (strange logic)

　　I found this method earlier, but just wanted to do it better (mainly the boot disk is better), so I have been
writing this boot disk these days. When it is relatively complete, I will announce this discovery.

　　But during helping calV, I encountered a strange thing. I found that this method couldn't succeed at the beginning! But then it ran
successfully. In order to find this reason, I decided to announce it in advance.

　　If you have used Drive Image 5, you know that it restarts before working. The NT kernel system
is very obvious. Since PQDI cannot run under the NT kernel, then after restarting, it naturally enters the system it can run - DOS. But many people don't have other systems installed except 2000/XP systems. Where does this DOS come from?

　　According to analysis, it has a program that can boot the system to a virtual floppy (a lot of ink is saved here), this virtual floppy actually uses the VFD format image (saved again). The other program he配, VFeditor.exe, which is the PowerQuest OEM version of WinImage, is used to edit it. My inspiration was caused by this.

　　Since he can boot the system to a virtual floppy, then the future boot disk can be replaced by him. When the local machine cannot use the floppy drive/CD-ROM drive for some reason, such as a ultra-thin notebook, no light and soft are brought for a while, and then you need to boot to DOS to do some operations (such as reinstalling the system,杀毒), it will be very convenient (because it seems that no virus said it can infect the VFD image, so
security is the same as CDRW).

　　The introduction is said to this point, and it is actually left for everyone to try. I put a temporary version for calV this time. The perfect version of the image will probably be announced in a few days.

　　For those with NT system kernel and interested
Just go and try it. Remember that successful operation will automatically restart, and then you will see the effect of this temporary version.

　　If it is not successful, you are welcome to propose, and I will go to improve.

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　THX

Quote from 8cat's post:
******************************************
Is the usage method like this:
Run the main program vfinstnt.exe under Win2k (automatically back up the partition table), restart, enter DOS, then perform relevant operations. After the operation is completed, restart, and the original partition table can be repaired.

Doubts:
If during entering DOS, reinstalling 2000, and some operations on the boot sector during the installation of 2000, will it affect the partition table of this software? Will it not recognize the original partition table after BOOT?
If there is no problem like this, then can PQ be used?
BTW, I also want one
*********************************************************************

PM,

It is estimated that it should be like this. To add, the partition table should be restored immediately after booting DOS.

Of course not. Originally, the program in this image is PowerQuest Drive Image 5. Can it not modify the partition table? Naturally not.
PQ can be used naturally.

Finally, I've figured it out. The purpose of "vfloppy -1 vloader.bin -2 vmemdsk.bin -i dos.img" is to reconstruct the two files "vloader.bin" and "vmemdsk.bin" based on the existing "dos.img" file. So, if you want to boot with a different IMG file, you just need to change these three filenames, but the filenames can't exceed 8 characters. For example, the command "VFloppy -1 VL_RST.bin -2 VMD_RST.bin -i RST442.img" reconstructs the "VL_RST.bin" and "VMD_RST.bin" files based on the existing "RST442.img" file. Of course, before that, you need to copy "vloader.bin" and "vmemdsk.bin" and rename them to "VL_RST.bin" and "VMD_RST.bin". So now I add a line "C:\VFloppy\VL_RST.bin="Ram Stress Test 4.42"" in BOOT.INI, and then I can boot with "RST442.img"!

The content of my "BOOT.INI" file is as follows:


timeout=5
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS

C:\VFloppy\VLoader.bin="MS-DOS 7.10"
C:\VFloppy\VL_RST.bin="Ram Stress Test 4.42"
C:\Bootsect.cdr="BOOT From CD-ROM"
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /noguiboo

The first line is to boot the virtual floppy with the "DOS.IMG" file, and the second line is to boot the virtual floppy with the "RST442.img" file.

Edited by Zuima on 08-20-2003 01:38:45; this post is a repost.

The advantages of VFLOPPY need not be mentioned, but its disadvantages are two: it does not support 1.68MB floppy disk IMG files and does not support writing functions. Now I am working on adding these two functions to GRUB for DOS.

It would be nice if grub could support img files of any size like bcdw does.

Download of bootsect.cdr mentioned in "C:\Bootsect.cdr="BOOT From CD-ROM"":
The file to boot from the CD.
Open the attachment
Usage: Put this file in the root directory, and add a line after Boot.ini

C:\Bootsect.cdr="Boot from CD-ROM"

Function: Scan from drive A to CDROM once, and try to boot the system.

Note: Cannot replace the CDROM function in BIOS settings. If this item is not in BIOS, the boot will not be successful.

I am not responsible for any liabilities regarding this file. If you can use it normally, it is your luck. If not, I basically have no way. Don't come to me if there is a problem. But it has been tested and there is no problem here. There will be no problems in principle

VERY GOOD!THANK YOU!

The following is a quote from hunome on 2003-11-6 10:37:46:
It would be great if grub could support img files of any size like bcdw.

yes

grub will support img files of any size, such as 500M or 5G img files. The release of the next test version will be in December 2003. Friends who are interested must be sure to participate in the testing!

The Chinese development homepage is at the following address:
http://www.linuxeden.com/edu/doctext.php?docid=3006

Great, support!

The latest test version of GRUB has been made. Some functions are not yet implemented, for example, the operation of formatting the virtual disk is prohibited.

This is only for testing purposes and should not be used formally because it may be dangerous. Please test and run it in VMWARE.

For detailed instructions, please see the following webpage:

http://www.linuxeden.com/edu/doctext.php?docid=3006

Who is willing to be one of the first people to participate in the test? Give me a space, and I will upload it?

I don't want to make it public now because it's too dangerous. I hope that people who test will not spread it as a stable version either. Thank you.

ftp://soft:down@wangdef.xicp.net/Upload

Dude, the address provided by you can't be used for uploading. I tried multiple times and it didn't work. I've already uploaded it here:

ftp://ftp.cosoft.org.cn/incoming/grub_t01.exe

Originally, I should have tested it first, but after I finished developing it, I didn't have time to test anymore. I've been really busy with work recently. Could you please help test it for me? But be extremely careful, don't damage the valuable data in your real machine. The testing will take about half a month, and after fixing some bugs, it will be next month. Then we'll test it on a larger scale. Thanks, dude!!

___________________________

After using ftp://ftp.cosoft.org.cn/incoming/grub_t03.exe, oh------, one of my hard disk images and two floppy disk images have been damaged!! Fortunately, I was also testing in VMWARE, so there was no real loss. Everyone must be careful!!

t01 and t02 are also definitely dangerous.

The cause hasn't been identified yet. If it can't be identified for a long time, the public release will be postponed.

I hope that the advantages of GRUB for DOS and VFLOPPY can be fully combined, because their functions are originally relatively similar in terms of virtual floppy disks, but each has its own advantages and disadvantages.

Is there a way to boot from a CD ISO image file on the hard drive???

Not possible right now. Hope to do this when I have time in the future.