Jim Henderson wrote:
>>> Thing is, it shouldn't require a change to the active partition list.
>> It doesn't *require* it. It *allows* it.
> 
> No, I mean in order to boot a different partition.

Windows and GRUB are the same in this respect. If the active partition 
is, for some reason, unreadable, you won't get a menu to boot the other 
partition. However, you can use a non-OS tool (fdisk off a dos disk, 
say) to change the active partition and boot the other OS.

It's a two-stage boot. You're talking about the second stage. I'm 
talking about the first stage.

> Probably, yes - though it's probably easier to modify the Grub setup at 
> that point and just add the Windows install.  Most people I know who 
> install Windows second, though, use a VM rather than a native boot.

There are definitely more options now than there were, yes. :-)

> It means that GRUB on my system here is using the active partition.  I 
> don't know what's in the MBR on this laptop's hard drive, but the 
> settings when I go into YaST and look indicate that it's installed to the 
> first sector of the active partition.

It's most likely installed to both. It's a two-stage boot. Maybe that's 
what's confusing the conversation.

The first stage is to load the MBR off (basically) sector zero of the 
hard drive, which happens to include the partition table. The *stnadard* 
MBR then looks at the partition table, finds the active partition, moves 
itself out of the way, reads the first sector of the active partition 
into the same place it was, and jumps to it.

Only after that second step do you get any kind of menu. If you delete 
NTLDR or /boot off the active partition, you're not going to have an 
opportunity to boot off a different partition. With the standard MBR, 
you don't have to put NTLDR or /boot back, you just have to change the 
active flag.  Last I experiemented, the GRUB MBR booted the GRUB 
partition even if it wasn't marked active, which means if your GRUB 
partition is corrupt, you're SOL.

-- 
Darren New / San Diego, CA, USA (PST)

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