Re: [help-a-newb] setting grub

[Joel Rees <joel.rees@gmail.com>]

On Sat, Apr 16, 2011 at 8:19 PM, Tom H <tomh0665@gmail.com> wrote:
> On Sun, Apr 10, 2011 at 11:04 PM, Joel Rees <joel.rees@gmail.com> wrote:
>> On Fri, Apr 8, 2011 at 9:18 PM, Tom H <tomh0665@gmail.com> wrote:
>>> On Thu, Apr 7, 2011 at 8:38 AM, Joel Rees <joel.rees@gmail.com> wrote:
>>>> On Thu, Apr 7, 2011 at 7:58 PM, Tom H <tomh0665@gmail.com> wrote:
>>>>> On Thu, Apr 7, 2011 at 3:02 AM, Joel Rees <joel.rees@gmail.com> wrote:
>
>
>
>>>>> The grub2 developers decided that most people wouldn't want to set up
>>>>> chainloads and would want update-grub to add all the available
>>>>> installs to grub.cfg to be directly bootable.
>>>>
>>>> That's kind of the way it looks, which is kind of shocking to me.
>>>
>>> If I were to hazard an estimate, I'd say that you're in a very small minority.
>>
>> If I were to hazard a guess, I'd say that I don't care if I am in the
>> minority. Proper engineering principles are proper engineering
>> principles.
>
> They must have to target what they can given the resources at hand.
>
>
>
>>>>> Renaming 30_os-prober's a good solution too, although it doesn't solve
>>>>> the BFO problem without some intervention form your side but nothing
>>>>> else does.
>>>>
>>>> Short of moving Debian off the first drive. Although the tutorial I
>>>> linked to above suggests that grub2 doesn't like to be called from
>>>> legacy grub.
>>>
>>> Strange tutorial. Claiming that "grub2 doesn't like to be called from
>>> legacy grub" doesn't make any sense.
>>
>> Didn't make any sense to me, either. But the official manual seems to
>> say similar things, and my experience over the last 5 days learning
>> more about grub than I wanted, well, I'm not going to argue with them.
>>
>> Fedora's legacy grub had similar problems to Debian's grub2 when it
>> came to finding something to boot on the 3rd drive. I got a message
>> about trying to access boot code beyond the BIOS limits at one point.
>> The controller card is a cheap raid card that I decided not to hang a
>> raid off of. (Maybe I should go master/slave on the first channel
>> instead of trying to use the second channel.)

If I go master/slave on the first channel, Debian's grub2 can boot the
third drive. (At least, it did so last weekend.)

I don't like that option for the usual reasons, and the manual for the
card agrees with me, says if I only have two drives I should attach
them to primary on each channel.

>>> This is the default behavior when
>>> you upgrade from grub1 to grub2.
>>
>> Never had that experience of upgrading, but how so?
>
> When you install grub2, one of the debconf screens asks whether you
> want to install grub2 to the MBR or chainload grub2 from grub1. (I'm
> paraphrasing.) If you choose the latter, grub1's menu.lst will have a
> stanza with "kernel /boot/grub/core.img" to chainload grub2.

I'm not sure what the point of that would be relative to what I'm trying to do.

>>> Do you mean calling grub1 from grub2? (The latter's not my experience
>>> either - but "it works for me" isn't really proof of anything.)
>>
>> If you know the incantations to get grub2 to chain to legacy grub,
>> could I ask you to post how you did it?
>
> >From memory, 40_custom:
>
> #! /bin/sh
> cat << EOF
> menuentry "Chainload Fedora grub1" {
> search --no-floppy --fs-uuid --set=root uuid-of-fedora-boot
> chainloader +1
> }
> EOF

Okay, I finally got a chance to try that. As it is, it does not
chainload itself. Gives me an error about a bad signature and says
"type any key", and if I do, it takes me back to the grub menu.

Trying that on the other two drives, the ones with Fedora on them,
just leaves the debian splash screen on the terminal forever.

Also tried "set root=uuid and that got the screen to go black and
leave a horizontal cursor in the top right-hand corner.