GRUB, how to prohibit modification and editing at the boot interface - China DOS Union Forum

GRUB, how to prohibit modification and editing at the boot screen. We are in an internet cafe, fearing that someone might delete our password to enter DOS and then enter DOS.

You can read the GRUB manual to see how to use the password.

Also, the DUCE parameter needs to be noted.

GRUB4DOS has a debugging function. Pressing c at boot time immediately enters the command line, skipping any menu.lst and the built-in menu.lst. This function is called "enter command line unconditionally". This function can be disabled, and the way to disable it is to use the --duce parameter. Both bootlace and grub.exe have this parameter. You can check the documentation to understand it clearly.

If you are using grldr or grldr.mbr in boot.ini or in Vista, then corresponding to --duce, you need to modify the control byte at the beginning of grldr or grldr.mbr. The specific description of the control byte is also in the readme file.

[ Last edited by 不点 on 2008-5-19 at 09:10 AM ]

Thanks to the friend above, it's already done. Adding a password in front of the menu works. The DUCE parameter is still not used. The description file found these related to duce are all in English, which I don't understand very well.
*** grldr.mbr - Details about the control bytes ***
******************************************************************************

Six bytes can be used to control the boot process of GRLDR.MBR.

Offset Length Description
====== ====== ==============================================================
02h 1 bit0=1: disable the search for GRLDR on floppy
bit0=0: enable the search for GRLDR on floppy

bit1=1: disable the boot of PREVIOUS MBR with invalid
partition table(usually an OS boot sector)
bit1=0: enable the boot of PREVIOUS MBR with invalid
partition table(usually an OS boot sector)

bit2=1: disable the feature of unconditional entrance to
the command-line(See below `--duce')
bit2=0: enable the feature of unconditional entrance to
the command-line(See below `--duce')

I am using GRUB to boot at startup. There are two GRUB menus: one to enter XP and one to boot DOS. The default is to boot XP in 1 second. Now I found another problem: pressing any key at startup shows the GRUB boot menu. I wonder if it can be changed so that the GRUB menu is only displayed when pressing F8 or a specified key.

[ Last edited by dwh2008 on 2008-5-19 at 03:20 PM ]

Floor1　dwh2008	Posted 2008-05-19 00:13
新手上路　Posts 2　Credits 6
GRUB, how to prohibit modification and editing at the boot screen. We are in an internet cafe, fearing that someone might delete our password to enter DOS and then enter DOS.

Floor2　不点	Posted 2008-05-19 08:48
银牌会员　Posts 1,115　Credits 2,491
You can read the GRUB manual to see how to use the password. Also, the DUCE parameter needs to be noted. GRUB4DOS has a debugging function. Pressing c at boot time immediately enters the command line, skipping any menu.lst and the built-in menu.lst. This function is called "enter command line unconditionally". This function can be disabled, and the way to disable it is to use the --duce parameter. Both bootlace and grub.exe have this parameter. You can check the documentation to understand it clearly. If you are using grldr or grldr.mbr in boot.ini or in Vista, then corresponding to --duce, you need to modify the control byte at the beginning of grldr or grldr.mbr. The specific description of the control byte is also in the readme file. [ Last edited by 不点 on 2008-5-19 at 09:10 AM ]

Floor3　dwh2008	Posted 2008-05-19 15:18
新手上路　Posts 2　Credits 6
Thanks to the friend above, it's already done. Adding a password in front of the menu works. The DUCE parameter is still not used. The description file found these related to duce are all in English, which I don't understand very well. * grldr.mbr - Details about the control bytes * ****************************************************************************** Six bytes can be used to control the boot process of GRLDR.MBR. Offset Length Description ====== ====== ============================================================== 02h 1 bit0=1: disable the search for GRLDR on floppy bit0=0: enable the search for GRLDR on floppy bit1=1: disable the boot of PREVIOUS MBR with invalid partition table(usually an OS boot sector) bit1=0: enable the boot of PREVIOUS MBR with invalid partition table(usually an OS boot sector) bit2=1: disable the feature of unconditional entrance to the command-line(See below `--duce') bit2=0: enable the feature of unconditional entrance to the command-line(See below `--duce') I am using GRUB to boot at startup. There are two GRUB menus: one to enter XP and one to boot DOS. The default is to boot XP in 1 second. Now I found another problem: pressing any key at startup shows the GRUB boot menu. I wonder if it can be changed so that the GRUB menu is only displayed when pressing F8 or a specified key. [ Last edited by dwh2008 on 2008-5-19 at 03:20 PM ]