Configuring/using grub with grub-install and grub-mkconfig

[Chris Green]

On Mon, Nov 18, 2019 at 01:03:57PM +0100, Liam Proven wrote:
> On Sun, 17 Nov 2019 at 19:08, Chris Green <cl at isbd.net> wrote:
> >
> > I have been searching around (and asking questions) about how to add a
> > separate /boot partition.  As a result I have become steadily *more*
> > confused about the relationship between grub-mkconfig and grub-install.
> 
> Hi, Chris.
> 
> This is something that is fairly trivial to do at installation time.
> It's probably non-trivial afterwards.
> 
Yes, you're probably right. :-)


> So, I feel I must ask:
> 
> [1] Is a reinstall feasible?
>
Yes, but it would take a while to add all the extra bits and pieces
that I have added to the basic installation.  Thus it would save a lot
of time if I can avoid a complete re-install from scratch.


> [2] And, er, well... why?
> 
It's because I'm adding a fast SSD which will probably not be seen by
the BIOS and thus I can't boot from it.


> Anyway. What I _have_ done a few times is move /home into its own
> filesystem, post-install. That is non-trivial too. Doing it to /boot
> might actually be _easier_. As such, trying to translate the steps
> from what I've done before, I'd say:
> 
Moving /home is easy, I've done it quite often.


> [1] make your new /boot partition.
> [2] mount it somewhere else for now, e.g. /newboot
> [3] copy the contents of the old /boot directory into the new mountpoint
> [4] add the new filesystem to /etc/fstab
> [5] (extra step) install GRUB2 to the new /boot filesystem
> [6] tell your firmware to boot from the new partition not the old one
> [7] rename your old /boot directory to something else, e.g. /oldboot
> 
> *Make sure you have working boot media to hand with the same version
> of the OS on them!*
> 
> And then try it.
> 
The above sounds good to me, what I think I will do is try it on a
'spare' old system first to see if there are any gotchas and then I'll
try it on my 'real' desktop.


> In theory that's about it, I think.
> 
Yes, thanks Liam.  :-)

-- 
Chris Green