[Mageia-dev] Grub2 vs. Grub Legacy in M3

[Barry Jackson]

On 29/01/13 12:48, Frank Griffin wrote:

> I wasn't aware of the MBR gap.  I guess you're saying that the core.img
> that fits in it *is* filesystem-aware ?

Yes, depending on the modules built into it, which are normally correct 
for our purposes.

>
> Anyway, my point still stands: for anyone who just wants to have grub
> and grub2 partitons coexist on the same disk with either one in the MBR,
> chainloading will accomplish this without any downside that isn't
> already present in grub legacy.

Yes

  Grub2 may be the way of the future, but
> to *require* it to own the MBR is just misleading.

Yes, it only gives that impression. It does not need to be the primary 
bootloader.

To demonstrate this I made a fresh install of Mageia3 with only grub 
legacy installed and booted from MBR.
I then installed the grub2 package (nothing more) and added an entry for 
the grub2 bootloader to the grub legacy menu.lst. (as in the README)
I then re-booted and selected the grub2 entry from the legacy menu.
The grub2 menu launched and contained all my systems - including the new 
Mageia3.
Selecting Mageia3 launched the OS.
Likewise selecting Mageia2 (found automatically during install of grub2) 
launched that correctly.

The MBR has not been touched at all since the installation of grub 
legacy by the Mageia installer.

Note that I do not advocate this as a sensible route to multi-booting, 
since it takes no account of kernel updates - it is just a demonstration.

Barry