[gentoo-user] Re: grub error I've never seen in many installs

[Harry Putnam]

Hinnerk van Bruinehsen  writes:

>> Has something changed regarding using that kind of technique?
>> 
>> I can't figure out why grub would be looking for a GRUB drive on
>> /dev/sda1 as the error says:
>> 
>>   grub-install: error: cannot find a GRUB drive for /dev/sda1
>
>
> Did you mount /boot from inside the chroot environment? IIRC I got a
> similar failure when mounting /boot from outside the chroot...

Egad, that is almost certainly what is going on.

However, before seeing your post I came up with what I thought might
be a way to get around the whole problem presented in the errors.

I preserved my install on the initial disk created in vbox for the
install.

Shutdown the vbox vm, created a set of new disks but this time using
whole disks rather than carving up partitions.

So instead of 1 disk carved up... I now had 4 disks in the same sizes
as the original partitions.

Booted the install media.. copied the installed OS over to the new
disks.  But this time I was asking grub to intall itself on a disk
with a single whole disk partition.

It all worked, ... but I think now, after your comment, I probably
mounted boot in the proscribed way this time around.  That is, from
inside a chrooted terminal.

Probably didn't need all the disk switching and copying at all.

Thanks for your input...

I'll know not to think I remember all about how to do this and pay
more attention to the install instructions. Even though I have done
this quite a few times... its usually been separated by along enough
time period that I might will have forgotten some of the necessary
steps.

Thanks again for taking time to post your thoughts.

Re: [gentoo-user] Re: grub error I've never seen in many installs

[Hinnerk van Bruinehsen]

On Wed, Jul 12, 2017 at 05:57:58PM -0400, Harry Putnam wrote:
> Arve Barsnes  writes:
> 
> > On 10 July 2017 at 22:06, Harry Putnam  wrote:
> >
> >>  grub-install /dev/sda Installing for i386-pc platform.
> >> grub-install: error: cannot find a GRUB drive for /dev/sda1.  Check
> >> your device.map.
> >>
> >> Where might I find `device.map'... it isn't part of grub2.  At least
> >> grep doesn't find it with `qlist grub'
> >>
> >
> > As far as I understand it, grub2 will dynamically create the device.map
> > when it needs it, so it doesn't actually exist as a file. On my grub legacy
> > system it is installed as /boot/grub/device.map, with the only contents
> > being "(hd0)   /dev/sda".
> >
> > How you would feed grub this information *before* it is installed I'm not
> > sure, but maybe look into the USE=device-mapper flag, maybe it installs the
> > grub-mkdevicemap executable.
> 
> Yeah, I tried that before posting.. setting USE=device-mapper then
> reinstalled grub2... same result as without the flag.  Same error
> message.
> 
> I've always .. on many installs (over time) and mostly into a vbox vm,
> created a disk, then when booting the install media I carve it up with
> fdisk.
> /dev/sda1=boot
> /dev/sda2=swap
> /dev/sda3=home
> /dev/sda4=/
> 
> Has something changed regarding using that kind of technique?
> 
> I can't figure out why grub would be looking for a GRUB drive on
> /dev/sda1 as the error says:
> 
>   grub-install: error: cannot find a GRUB drive for /dev/sda1


Did you mount /boot from inside the chroot environment? IIRC I got a
similar failure when mounting /boot from outside the chroot...

[gentoo-user] Re: grub error I've never seen in many installs

[Harry Putnam]

Arve Barsnes  writes:

> On 10 July 2017 at 22:06, Harry Putnam  wrote:
>
>>  grub-install /dev/sda Installing for i386-pc platform.
>> grub-install: error: cannot find a GRUB drive for /dev/sda1.  Check
>> your device.map.
>>
>> Where might I find `device.map'... it isn't part of grub2.  At least
>> grep doesn't find it with `qlist grub'
>>
>
> As far as I understand it, grub2 will dynamically create the device.map
> when it needs it, so it doesn't actually exist as a file. On my grub legacy
> system it is installed as /boot/grub/device.map, with the only contents
> being "(hd0)   /dev/sda".
>
> How you would feed grub this information *before* it is installed I'm not
> sure, but maybe look into the USE=device-mapper flag, maybe it installs the
> grub-mkdevicemap executable.

Yeah, I tried that before posting.. setting USE=device-mapper then
reinstalled grub2... same result as without the flag.  Same error
message.

I've always .. on many installs (over time) and mostly into a vbox vm,
created a disk, then when booting the install media I carve it up with
fdisk.
/dev/sda1=boot
/dev/sda2=swap
/dev/sda3=home
/dev/sda4=/

Has something changed regarding using that kind of technique?

I can't figure out why grub would be looking for a GRUB drive on
/dev/sda1 as the error says:

  grub-install: error: cannot find a GRUB drive for /dev/sda1