Arch Linux

i336

Member

Registered: 2011-01-08

Posts: 11

Making NTLDR / GRUB play nice together

Hey...

I need to run a few Win apps so decided to try getting Win2k working again - I'm not taking this venture *too* seriously, and will certainly not try to use the 'Net too much from W2K, I just need to run some software that most decidedly will not work in Wine. And I don't think this PC would take too kindly to virtual machines. So W2K it is. After all, I have it installed... so why not use that? That's enough of the NT codebase to get what I want working.

I'd basically like to get a vague sort of idea as to how to get both to work happily from either the NTLDR menu, or the GRUB menu. At the moment I'm selecting which OS I want from the BIOS, since W2K is stuffed amongst a library of partitions on a spare disk. I haven't yet properly tried to boot Arch, ie GRUB, through NTLDR, since I'd really like to go the other way, yet every time I try to boot the disk from the grub command prompt I just get met with different errors - either from doing "root (hd1)" or "root (hd1,3)" - I don't remember what the errors say, but they more or less culminate in "NTLDR got confused" (like that helps).

So if anyone has any ideas on how to get NTLDR happy booted from GRUB, or can offer any suggestions as to why it might not be booting, or tests I can do, etc, that'd be great. As it stands NTLDR stubbornly refused to play nice unless I made the spare disk the primary master; after fixing Arch's very loud indigestion due to fstab at that point being incorrectly configured, at least Linux is working again, haha. But I'd prefer to be able to boot from a menu, not the BIOS, as you can understand.

Anyway, I turned the computer on this session to be greeted with a decidedly kaput W2K installation; I have no idea why. I march off in the general direction of figuring this new development out and hopefully fixing things.

-i336

Last edited by i336 (2011-09-21 07:37:40)

PaulBx1

Member

Registered: 2008-10-18

Posts: 142

Re: Making NTLDR / GRUB play nice together

This might give you some ideas:
http://www.icpug.org.uk/national/linnwin/contents.htm

For the XP case he has ntldr call grub which then boots linux. Not sure why ntldr cannot boot linux directly, but if you read through there it may explain somewhere.

stoat

Member

Registered: 2011-08-07

Posts: 12

Re: Making NTLDR / GRUB play nice together

So if anyone has any ideas on how to get NTLDR happy booted from GRUB, or can offer any suggestions as to why it might not be booting...

When you set the BIOS drive order to boot Arch, the W2K drive becomes a non-first drive. In that situation, use need to use the map menu command in menu.lst to virtually swap the Windows drive to first. Then W2K will boot from GRUB. An example for if W2K's boot loader files were located in the first partition of the second drive...

title W2K
rootnoverify (hd1,0)
map (hd0) (hd1)
map (hd1) (hd0)
chainloader +1

Or for the third drive......

title W2K
rootnoverify (hd2,0)
map (hd0) (hd2)
map (hd2) (hd0)
chainloader +1

And so on.

I'd basically like to get a vague sort of idea as to how to get both to work happily from either the NTLDR menu, or the GRUB menu.

To go the other way and boot Arch with NTLDR, there is a well-known free utility known as BOOTPART that will somewhat ease the configuration chore. It runs in a Windows Command Prompt window and is not a pretty GUI app. But it's very handy. It will create in the W2K root directory a binary file with code that will launch GRUB stage1 which you first have to install or re-install in the first sector of the Arch boot partition (or root partition if no separate boot partition). And then BOOTPART will edit W2K's boot.ini file to add an entry to launch the binary file.

Not sure why ntldr cannot boot linux directly.

If you mean why it cannot directly boot the linux kernel, it's because it exists in a filesystem not accessible by NTLoader. That is why BOOTPART creates the binary file in the root directory of Windows. Another common and more manual technique is to use dd to copy stage1 from the first sector of the Linux system's boot partition to a binary file in the Windows root directory and manally edit boot.ini to add a menu entry to launch it.

Last edited by stoat (2011-09-26 02:27:32)

i336

Member

Registered: 2011-01-08

Posts: 11

Re: Making NTLDR / GRUB play nice together

Life *HAS* been hectic lately, wow. This is the first time I've been able to get to the computer in quite a while...

Well, I'm in Win2k.

Thanks very much.

-i336

Last edited by i336 (2011-10-10 05:11:07)