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Grub: two OS with two HDs?

I'd like to migrate my wife's computer to Linux (my 2 year old daughter is already a Linux fan), so I decided to install a dual boot option Debian / win.

Win was already installed in a HD, so I switch that hd off and installed Debian in another HD. Then, I connected both hard disks with both OS installed separatedly. I tried to setup Grub (in /boot/grub/menu.lst) but I didn't find the clue to boot up using both OSs.

It is posible to configure grub to boot with many OSs installed this way ("separatedly": first one hd, then the other)?

Editing menu.lst is enough or it is necessary to configure anything else?

Thanks in advanced,
Matías

since you installed Debian in the 2nd drive, I assume that you put GRUB there also. I'm also assuming that---with the 1st drive connected--you can still boot Windows.

You have at least 2 options:
1. If the BIOS can be configured to select which is Drive #1, then you can do multi-boot that way.

2. Do whatever you have to to get it to boot from the Linux drive--eg you might simply switch the cabling/jumpers.

Once you are in the Linux system (by any method), (IF GRUB IS NOT ALREADY ISTALLED) then install grub like so: (I'm assuming 2 ide drives--#1Linux, #2 Windows)

Code:

grub  (starts the grub shell)

root (hd0,0)  (tells grub that it's home base is on the 1st drive, partition #1**)

setp (hd0)  (puts grub in the mbr of drive 1)

Now, you need to configure grub so that it will boot windows:
open /boot/grub/menu.lst with a text editor
Create (or edit) and entry that looks like this:

Code:

title Windows

  rootnoverify (hd1,0)

  map (hd0) (hd1)

  map (hd1) (hd0)

  chainloader +1

  makeactive

  boot

The two map commands are required because you have Windows on drive 2.

**Note that grub counts from 0....

Why did you disconnect the drive with Windows on it?

The easiest way - and since you haven't invested any time into Debian yet maybe reinstall - is to leave the Windows drive connected and install Debian. During the Debian installation, it will prompt you to partition the drives, leave the Windows drive untouched, and tell the Debian Installer to install to the second hard drive.

At the end of the install process, as part of boot loader installation, Windows should be detected. Install GRUB to the MBR of the first hard drive. When you boot your machine, you will get a GRUB screen, and you can select from Linux or Windows.

I hope this helps
--Ian

Thanks a lot for the help!!

Tomorrow I'll try to setup Grub as you say.
I think there's a lot to learn on Grub for a newbie as me. I'll look for a good tutorial.

I imagined that installing Debian or any other distro with the win HD connected the intall process should detect that win...
I followed that extrange install procedure because first I had decided to try Debian with Xfce in a quite old computer, and it worked fast! Then, I decided to make a dual boot.

Thanks,
Matías

Pixellany,

I followed your advice and it worked great! I'm now able to make the dual boot and choice between both OS.

Thanks a lot!
Matías