Grub4dos Guide - Introduction


All 32-bit utilities used in the guide have been tested on a Windows XP system, all DOS utilities have been tested with a Windows 98 SE based boot disk. Compatibility with other operating systems can not be guaranteed.

Throughout the guide any text with a      highlight (e.g. C:\grldr), is a file and/or path. It can also indicate a folder that needs to be created.

Any text with a      highlight (e.g. find --set-root /grldr), is a command.

Any text with a      highlight (e.g.  grub> help --all ), is output from a screen (e.g. Grub4dos feedback).

Any text within [ ] brackets is a keyboard input - e.g. [tab] = press "Tab" key.

Grub4dos is a continually evolving project, therefore some of the information contained in this guide may not apply to previous versions, or be applicable to future versions.

The guide is not intended to cover all Grub4dos features, neither is it intended to replace the README_GRUB4DOS.txt file which is included in the Grub4dos package. The guide is meant to be a starting point and covers the syntax and some of the more commonly used commands - hopefully after gaining an understanding of the commands covered in the guide the user will have the confidence to experiment further.

A quick note on printing the guide - make sure printing background colours and images is enabled within your browser, or text highlights (for commands and files etc) will not be printed.


GRUB4DOS is a universal boot loader based on GNU GRUB. It can be used via a command line interface or menu, and has many features including -

Unlike GNU GRUB, which relies on several Stage files, the Grub4dos functions are built into a single file grldr (or grub.exe if booting from DOS or Linux). grldr can be loaded via an existing operating system - e.g. via the NT loader ntldr during the Windows NT/2000/XP boot process. Alternatively grub4dos code can be written to the mbr or partition boot sector of a device.

To simplify the boot process, if Grub4dos code is installed to the MBR of a hard disk type device, then all (supported) hard disks/partitions and floppy devices are scanned for grldr. Supported file systems include

If Grub4dos code is installed to a partition boot sector then grldr must be present in the booted partition.

If Grub4dos code is installed to a CD or Floppy device, then grldr must be present on the boot device.

Once grldr or grub.exe is loaded, an embedded menu is executed. This menu searches for the Grub4dos configuration file menu.lst. If menu.lst is not found then a command shell is started.

For a more detailed explanation of the boot process (and embedded menu) see here.

Unfortunately there is (currently) a lack of documentation available for Grub4dos - a readme file is included in the grub4dos download package and a useful guide is available from sourceforge. A Linux focused guide is available here. Forums are also a good source of information, in particular the 911cd forum and boot-land (which has a Grub4dos sub forum here).