Re: Grub2 booting Dell Diagnostics

[Andrei Borzenkov]

В Thu, 05 Mar 2015 19:56:36 +0100
Ole Reier Ulland <address@hidden> пишет:

> I have sent this e-mail to address@hidden without getting any useful 
> replies, so now I try this e-mail-address.
> 
> The computer is a Dell Dimension 8300, with a SATA HDD with Grub2, Linux and 
> data partition, and a IDE HDD with Dell Diagnostics, Windows and data 
> partition.
> 
> I had to give up on Grub because Grub seems not to be able to boot Windows on 
> a different HDD than where the Grub is, and bios is not able to start Grub on 
> an IDE HDD when there is a SATA HDD.
> 
> I attempt to have the "Dell Diagnostics" partition to be bootable from Grub2 
> menu.
> 
> Grub2 produces an option for booting Windows in the menu that is not in the  
> /boot/grub2/custom.cfg file. What I have done is to make a copy of the 
> automatically produced menu entry and made one myself in the custom.cfg file. 
> An identical copy booted Windows. So now is the question of how to change it 
> so it will boot the other partition on the same HDD. I changed the menu line, 
>  
> "msdos2" to "msdos1" since I am now booting the first partition and not the 
> second, and the UUID. I believe those to be correct, but what remains is the 
> file system type.
> 
> QUOTE from /boot/grub2/custom.cfg,
> 
> menuentry 'Dell Diagnostics (on /dev/sda1)' {
>     insmod part_msdos
>     insmod fat
>     set root='hd0,msdos1'
>     if [ x$feature_platform_search_hint = xy ]; then
>         search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-
> efi\=hd0,msdos1 --hint-baremetal=ahci0,msdos1 O7D4-0318
>     else
>         search --no-floppy --fs-uuid --set=root 07D4-0318
>     fi
>     drivemap -s (hd0) ${root}
>     chainloader +1
> }
> 
> END QUOTE
> 
> When Grub2 boots Mageia4 on file system id "83" (Linux) the menu says, 
> "insmod 
> ext2".
> When Grub2 boots Windows on file system id "7" (HPFS/NTFS/exFAT) the menu 
> says, "insmod ntfs".
> What shall I then use in the menu in "insmod xxx" when I want to boot Dell 
> Diagnostics on file system id "de" (Dell Utility)? Unless this booting needs 
> something else, that the Windows partition did not need, it is not "fat", 
> "vfat" nor "DellUtility".
> 
> As the menu entry is right now it only causes the computer to restart.
> 

According to results from bootinfoscript, Dell Diagnostic partition
appears to have a boot block. I tried to load it in grub2 and I was as
far as getting "Disk error" back which means it was actually loaded and
executed. Unfortunately we do not really know what program it loads
does. In the worst case it may even bypass BIOS in which case it could
be quite confused by finding extra disk.

If you want to troubleshoot it, I'd first try to boot diagnostic
partition without any additional hard disk. Create rescue image by using

grub2-mkrescue -o /tmp/grbu2-rescue.iso

and burning ISO to a CD. Unplug SATA disk, boot from this CD, you will
be in grub command line. Then do

set root=hd0,1
chainloader +1
boot

Does it boot?