Re: Dedicated grub2 partition

[Goh Lip]

On Sunday 03,October,2010 11:35 PM, Barry Jackson wrote:
> Goh,
> I have tried all ways to boot the PCLOS iso from grub2 and it either
> dies with kernel panic (can't find init) or cannot find the loop file
> which I assume is livecd.sqfs.
> In the legacy case I can see it being found on sda1 (it searches all
> available drives and stops at sda1 having found it) as that is where I
> extracted it.
> In grub2 I cannot figure a way to tell it to search the loop mounted iso
> for the livecd.sqfs (I remove it from mainboot for grub2 tests)
> The initrd runs fine and hardware detection is OK - until it tries to
> hand over to the live image.
> My last attempt was :-
>
> menuentry "iso test" {
> loopback loop (hd0,1)/pclinuxos-lxde-2010.1.iso
> linux (loop)/isolinux/vmlinuz boot=(loop)/livecd vga=788 fromusb
> root=/dev/sda1 acpi=on fstab=rw,noauto
> initrd (loop)/isolinux/initrd.gz
> }
>
> livecd.sqfs is in the root of the extracted iso.
>
> Any ideas?
>
> Barry

Barry, I do not use and I am not familiar with PCLinux, but I have a 
suspicion that PClinux uses 'casper'. If you can confirm this by 
checking the iso file by
"mount -o loop xxxxxpclinus.iso /mnt/xxxx"
and look into the boot file, you can find what the 'liveiso' (trying to 
avoid the term 'livecd' as the entry you use quote 'livecd' as 'boot 
method')

But I think it might help if I list below the menu entries of some of 
the iso boots I had used. But note I now do this rarely.


menuentry "Iso - Casper " {
search --no-floppy --label --set Cas
loopback loop /pop/kubuntu-maverick-amd64.iso
linux (loop)/casper/vmlinuz boot=casper 
iso-scan/filename=/pop/kubuntu-maverick-amd64.iso noprompt noeject quiet 
splash
initrd (loop)/casper/initrd.lz
}


Barry, note below

"Cas" is label name of paartition where the iso resides
you can of course use uuid
search --no-floppy --fs-uuid --xxxxxxxxxxxxxxxxxxxxxxxxxxx

2nd line- /pop/kubuntuxxxx --> 'pop' is folder where the iso is
if you put in /home, then it should be /home/<you>/xxxx.iso

Note too, in my case initrd ends with .lz not the usual .gz Check yours 
too carefully.

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

More examples where boot is not 'casper'


menuentry "grml-iso" {
  loopback loop (hd0,9)/pop/Apps/grml64_2010.04-rc1.iso
  linux    (loop)/boot/grml64/linux26 
findiso=/pop/Apps/grml64_2010.04-rc1.iso boot=live quiet  noeject noprompt
  initrd   (loop)/boot/grml64/initrd.gz



Note this case, I had use (hdo,x) but the casper method is better in 
using "search xxxxxxxx" (this was much earlier example, where I was 
experimenting) but note use of 'findiso'and the boot method is 'live'
where the 'live' was found after I "mount -o loop xxx.iso".
Again /pop(that'me)/Apps is folder where iso is.

Also 'findiso' is same as 'isofind',

Other boot methods include 'boot'  etc. Right now, I cannot find my 
entry for the rescuecd livecd. But I'll rush this off to you first.
If there's more, I'll let you know, but really have not done this for a 
long time.

Good luck and regards - Goh Lip