Re: grub2 & mdraid

[Andrey Borzenkov]

On Mon, Feb 10, 2014 at 1:59 PM, Oleg <address@hidden> wrote:
> On Mon, Feb 10, 2014 at 12:50:25PM +0400, Andrey Borzenkov wrote:
>> >
>> >      grub --modules="part_msdos raid mdraid1x" --root-directory=/mnt 
>> > /dev/sdb
>> >      grub --modules="part_msdos raid mdraid1x" --root-directory=/mnt 
>> > /dev/sdc
>> >
>>
>> Upstream does not have this command, you need to ask your
>> distribution. Also in general grub2 is intelligent enough to figure
>
>   Sorry, this is a typo - must be grub-install instead of grub.
>
>> out what modules it needs; you need to have very good reasons and
>> understanding of grub internals to manually specify them.
>>
>> Try using
>>
>> grub-install --boot-directory=/mnt/boot /dev/sdb
>> grub-install --boot-directory=/mnt/boot /dev/sdc
>
> This commands complains:
>
> touch: cannot touch '/boot/grub/grub2-installed': Read-only file system
> Installation finished. No error reported.
>

This is either downstream patch or command is wrapper around real
grub-install. In upstream grub-install never attempts to touch this
file.

> But now the system is booting ok. I test:
>
> grub-install --root-directory=/mnt /dev/sdb
>
> and the system boot again.
>
> Ugh... Now i can't understand anything. Early i tried various versions of 
> grub2
> and various command options and now i confuse myself.
>
> What is the difference between --boot-directory and --root-directory in my 
> case?
>

--root-directory is deprecated in current upstream, but that's
basically all. There should be no differences if using upstream
sources. As for your specific case, I do not know :)