I'm having problems getting grub2 to chainload Windows XP correctly. I have 3 hard drives. The first one has an embarrassingly old Ubuntu installation that still uses legacy grub. The second one has XP on one partition and Ubuntu 10.10 on the second partition. The third one is just a data drive so it doesn't pertain to this discussion. When I boot from the first drive I still get grub and can chainload XP just fine. However, when I boot from the second drive and get the grub2 menu if I select Windows it gives me an error "Windows could not start because of a computer disk hardware configuration problem. Could not read from the selected boot disk." I assume this error is coming from the Windows bootloader on my first hard drive.
Now, you might be tempted at this point to tell me "Oh, it's a problem with your Windows installation". Please understand that I cannot accept this answer unless you also explain to me why legacy grub still has no problem booting XP. It's particularly vexing to me how utterly simple the commands were to do this in the menu.lst of legacy grub, which never gave me any problems at all, whereas the commands that got generated in the grub.cfg for this are incomprehensible to me and some of them (i.e. drivemap) don't appear to have any documentation anywhere at all!
I apologize if this comes off as a bit of a rant, but I'm sure you can understand how frustrating it is when a new version of software is updated and in the process something that is simple and "just works" is transformed into something complicated that doesn't work at all. What I really would like to know is simply: what incantations do I need to give to grub2 to make it behave the same way that grub behaves when I simply tell it "root (hd0,0); makeactive; chainloader +1"
Here is some additional info that could help in diagnosing this situation:
menu.lst entry that works: title Windows XP Media Center Edition root (hd0,0) savedefault makeactive chainloader +1
grub.cfg entry that doesn't work (also note that 1cd7-3124 is the correct uuid for sda1): menuentry "Windows XP Media Center Edition (on /dev/sda1)" { insmod part_msdos insmod fat set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 1cd7-3124 drivemap -s (hd0) ${root} chainloader +1 }
boot.ini file that resides in sda1: [boot loader]
timeout=30
default=multi(0)disk(0)rdisk(1)partition(2)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(1)partition(2)\WINDOWS="Windows XP Media Center Edition" /noexecute=optin /fastdetect
And I don't know if it's important or not, but on my system it's sda that boots legacy grub and sdb that boots grub2.