Bug#491977: grub-probe fails with "Cannot find a GRUB drive for /dev/dm-N."

[Robert Millan]

On Tue, Jul 29, 2008 at 04:01:31PM +0200, Felix Zielcke wrote:
> Am Dienstag, den 29.07.2008, 15:50 +0200 schrieb martin f krafft:
> > also sprach Felix Zielcke <fzielcke at z-51.de> [2008.07.29.1541 +0200]:
> > > There are hopefully not many people who use the normal linux
> > > software raid to get there fake hardwarwe raid controllers to
> > > work.
> > 
> > One should hope dmraid never existed or will soon cease to exist.
> 
> Hm probable it wouldn't be a much differnet if you use dmraid or mdadm
> on the real sdN and hdN devices.
> The problem in this case is, dmraid created dm-N devices which map to
> the sdN and hdN devices (I have them too and I wonde why, I think there
> just the same as my sdN) and then he used mdadm with the dm-N devices.
> But if he wanted to use md raid instead of dmraid then he should have
> used the real sdN and hdN devices.
> But we have now the problem how to detect this and get GRUB working with
> it.
> It's a problem for us, if you use md raid on the dm-N devices.
> md raid on real sdN and hdN is working fine.

If this problem is uncommon or only affects users with a deprecated setup,
let's not worry about it.  GRUB 2 handles this in a completely different way,
so our effort is most likely not going to pay back.

-- 
Robert Millan

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