Re: Dedicated grub2 partition

[Goh Lip]

On Wednesday 06,October,2010 06:49 PM, Barry Jackson wrote:

> Hmm.. see my point earlier about rescue systems on sticks - I avoid them.
> If I boot from a CD then hd0 is sda1. If I boot from a stick, then the
> stick is sda1 and hd0 can be sdc - it's chaos.
> If I boot to my livecd in maingrub (sda1) everythig is just fine - all
> drive assignments are correct.
>
> Just on that point, can grub2 use labels instead of :-
> set root=(hdx,y)/...
> like :-
> set root=myrootlabel...
> or :-
> set root=LABEL=myrootlabel
>
> That would really be nice!

Yes, definitely! That's why I always use one of these....
search --no-floppy --fs-uuid --set xxxxxxxxxxxxxx
search --no-floppy --label --set xxx

I even remove
set root='(hd0,msdos7)' for example, even though its removal is not 
necessary.  But if you leave it there, make sure this is *above* the 
"search xxxxxxxxx" line, eg

set root='(hd0,msdos7)'
search --no-floppy --fs-uuid --set xxxxxxxxxxxxxx

So, booting up any disk or usb partition  by uuid or label is longer a 
'chancey' affair.

> Well I think this may be a no-go. I just read the log-on header to the
> #grub IRC channel - to quote :-
> "It is impossible to "boot" an ISO from disk unless that image
> specifically supports that" which probably indicates that they are fed
> up with people asking the question!
> So maybe the ones that do work have been built with this in mind. I will
> do some more reading.


I hope you are right on this. Hate to think that we cannot resolve this 
on our wits and persistence. :)     But, yes, some livecd insist on 
their particular way to boot iso, and some include passkeys as well. 
Found casper pretty reliable and its use of 'persistence' and casper-rw 
is quite useful.




> I only was testing it because of your suggestion. The other method of
> extracting isolinux and livecd.sqfs works fine.
>
> Out of interest :-
> I have also re-mastered a live cd from a working PCLOS installation
> (using mylivecd) after adding some extra tools, my user, and some custom
> configuration, and that one boots fine the same way. I had to increase
> the size of sda1 though for that to work as it was just too big for my
> 1GB partition.

Great, I remembered having trouble with this years back. But by 
installing to usb sticks (not live boots), seems to have made this moot 
(for me).

> Thanks for all your help, but I think we failed :-(
>
> Cheers, Barry

Had fun myself too, Barry; but I don't think we failed, to paraphrase 
Edison (I think), we succeeded in finding many ways that didn't work.  :)

Regards and take care - Goh Lip




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Life is a sexually transmitted disease with a 100% mortality rate.