Absolute OpenBSD: Unix for the Practical Paranoid

A boot manager is a program that controls which operating system boots on a computer. Previously, we used an active partition to tell the BIOS the partition to hand control to. A boot manager allows you to choose on the fly the partition you want to use. A computer with only one operating system on it does not need a boot manager, but if you've installed more than one OS you'll need one.

We're going to discuss GAG, the Graphical Boot Manager. GAG really is an acronym for Graphical Boot Manager — in Spanish, the author's native language. The program is astonishingly simple to manage and quite pretty to look at, and it works perfectly to boot any number of operating systems, including OpenBSD.

If you have a preferred boot manager that you are experienced with, use it! Linux and FreeBSD both include excellent boot managers, and the Windows NT boot manager can be used to handle OpenBSD partitions with a bit of research. I generally find that GAG is the simplest way to go for dual-boot OpenBSD/ Windows systems, however.

Finding GAG

GAG has a home page, at http://www.rastersoft.com/gageng.htm. You can find documentation here, as well as a variety of links to booting resources. Just download the zip file and uncompress it. You'll find a copy of the GAG license (GPL), a directory containing the GAG source code, a disk image, and rawrite.exe, the Windows program to burn a disk image to floppy.

The GAG disk image, disk.dsk, is a boot floppy image, much like the OpenBSD install disk. You can copy this image to a disk with any of the tools you used to create the boot floppy in Chapter 2. You should have your OpenBSD system up and running, so here's how to do it in OpenBSD.

# dd if=disk.dsk of=/dev/fd0c

Once you have the bootable floppy, boot from it. It should very quickly present you with a text-based menu system. You can find extensive documentation in the instructions available through this menu. Check out the instructions, and then hit the "install GAG" option ("4" in GAG 4.1). You'll have a chance to choose your keyboard layout, and your language, then GAG will bring up a nice graphic menu with two options:

Boot from Floppy Disk Key 1 Set up GAG Key S

You want to tell GAG about your system, so hit "S." This will bring up another text-based menu, with the "command letter" being highlighted in red. Choose "Add an Operating System," and you'll see a list of options much like this.

A Boot from floppy B 0Bh MS-Windows FAT32 C A6h OpenBSD

Hit "B" to tell GAG about your Windows system. It will ask you for a description to show on boot, and offer you a choice of graphic logos to choose from. You can repeat the process for to configure GAG to load OpenBSD as well, and even use the cute little blowfish logo.

When you're done, be certain to tell GAG to save the setup in the hard disk.

The next time you boot, you will get a graphic menu offering you both operating systems on your hard drive.

You can also configure GAG to load a default operating system and to boot that default after a certain number of seconds, or just about anything you would like.

Congratulations! You now have a full dual-boot system.