Re: Exercise: Booting from a LiveUSB ISO and contents on /dev/sda6

[Fajar A. Nugraha]

On Mon, Nov 2, 2015 at 12:36 PM, Jordan Uggla <address@hidden> wrote:

On Mon, Nov 2, 2015 at 3:27 AM, Philip Rhoades <address@hidden> wrote:
> People,
>
> I want to enlarge my root partition on a Fedora 23 x86_64 system and I know
> I can boot on a LiveUSB stick and use [g]parted from there to do what I want
> but I thought I would try creating a small partition with the ISO and its
> contents in it to see if I could do what I want without needing to use the
> USB stick.

Since this is an end user support question, rather than a patch or
discussion about developing grub, it should be posted to
address@hidden rather than grub-devel. I have CC'd helo-grub. In
your replies, please include help-grub and *remove* grub-devel from
any further replies. This problem is also actually more Fedora
specific than grub related, as explained below.

>
> The contents of /dev/sda6 is:
>
> dr-xr-xr-x   3 root root       4096 May 22 05:03 EFI
> dr-xr-xr-x   2 root root       4096 May 22 05:05 LiveOS
> dr-xr-xr-x   2 root root       4096 May 22 05:03 isolinux
> drwx------   2 root root      16384 Nov  2 06:08 lost+found
> -r--r--r--   1 root root       2460 May 22 05:04 Fedora-Legal-README.txt
> -rw-r-----   1 qemu qemu 1007681536 Oct  7 20:14
> Fedora-Live-Xfce-x86_64-22-3.iso
> -r--r--r--   1 root root       1063 May 22 05:04 LICENSE
>
>
> I have made a little progress but I still can't get a boot - here is the
> current state of the relevant section of my grub2.cfg (I have been trying
> various changes):
>
> menuentry "Fedora 22 XFCE ISO Boot (x86_64 bit)" {
>     insmod part_gpt
>     set isoname="Fedora-Live-Xfce-x86_64-22-3"
>     echo $isoname
>     set isofile="${isoname}.iso"
>     echo $isofile
>     loopback loop (hd0,gpt6)/$isofile
>     echo $loop
>     linux (loop)/isolinux/vmlinuz0 root=live:CDLABEL=${isoname}
> rootfstype=auto ro rd.live.image rd.luks=0 rd.md=0 rd.dm=0
> iso-scan/filename=${isofile}

iso-scan/filename= is a kernel parameter that Fedora does not support,
as Fedora does not support loop booting (booting from the iso file on
a filesystem rather than burned to a DVD or extracted to a hard

Is that a regression?

These links suggest that you can boot fedora from iso, with iso-scan/filename.

https://ask.fedoraproject.org/en/question/33055/boot-fedora-20-from-iso/

https://tlhp.cf/multiusb-flash_drive/

https://wonderneko.wordpress.com/2015/09/17/boot-iso-fedora-22-via-grub-ubuntu-14-04/

drive). Please file a bug report against Fedora asking them to add
such support, or extract the iso (which you have also done already),
or use a distribution that supports loop booting such as Ubuntu. For
instructions on loop booting an Ubuntu iso (or any other iso which
ships with a loopback.cfg) please see
http://www.supergrubdisk.org/wiki/Loopback.cfg#How_do_you_use_a_loopback.cfg_to_boot_an_iso.3F
.

>     initrd (loop)/isolinux/initrd0.img
> }
>
> During the attempted boot I see the first two "echo"s but then get messages
> that "linux" and "initrd" commands do not exist . . is it something simple I
> am missing?

This is a Fedora specific problem, with upstream grub you would not
have this problem. I am not very familiar with Fedora's secure boot
setup, but I suspect that is the reason that the "linux" and "initrd"
commands are not available, and that instead you need to use
"linuxefi" and "initrdefi".

That's probably it.

-- 

Fajar