In addition to using the command line from within the GRUB menu interface (or booting directly to the command line), you can run a GRUB shell directly from the Linux command line with the grub command. For the most part, using the grub shell is the same as running in the native command-line environment. The major difference is that the shell uses operating system calls to emulate the BIOS calls that the native environment uses. That can lead to some differences in behavior.
The syntax of the grub command is:
The grub command-line options are:
Turn on batch mode for noninteractive use. Equivalent to grub --no-config-file --no-curses --no-pager.
Use drive as the Stage 2 boot drive, specified as a decimal, hexadecimal, or octal integer. The default is hexadecimal 0x0.
Use file as the GRUB configuration file. The default is /boot/grub/menu.lst.
Use file for the device map. The value of file is usually /boot/grub/device.map.
Display a help message to standard output and exit.
Wait for a debugger to attach before starting grub.
Use partition as the Stage 2 installation partition, specified as a decimal, hexadecimal, or octal number. The default is hexadecimal 0x20000.
Run without reading the configuration file.
Don’t use the curses interface for managing the cursor on the screen.
Don’t probe for a floppy ...