Re: GRUB only offers a rescue shell

[Pascal Hambourg]

Le 14/07/2017 à 06:15, Jordan Uggla a écrit :
> On Thu, Jul 13, 2017 at 1:20 PM, Pascal Hambourg <address@hidden> wrote:
> > Or one could force grub-install to include the part_msdos module in the core
> > image with the --modules=part_msdos option.
>
> One could, and it would work, but basically only by chance due to how
> cross disk installs are supported in grub. grub-install would still
> see it as a cross disk install, and would still set it up as such.
> Because cross disk installs use an embedded config that searches by
> UUID, and that search happens to still search partitions even when
> grub-install "knew" that $prefix was not to be found on a partition,

IMO it is a pity that GRUB does not also search by UUID even when the 
core image and $prefix are on the same disk. It would avoid boot failure 
when the partition containing $prefix is renumbered (logical partition 
numbers are not stable when you create or remove another logical partition).

> $prefix would be configured properly but it's an ugly work around that
> could break if grub's implementation changes. I am firmly of the
> opinion that the --modules option should never be used, as it is
> almost exclusively misused and it is easy to break things when using
> it.

I had to use --modules once on a regular setup because grub-install did 
not include some required module by itself.