Re: [Libreboot] Booting from usb/cd without grub graphics

[Bruno Dantas]

Yes, what you did seems much simpler and safer. Glad to hear you got the CD to 
boot. Hopefully it will work just fine from USB as well.

Just in case other people see this thread and decide to give my hack a try, I'd 
be careful with my suggested "grub entry to boot from grub" idea: Without being 
able to see the output of a "ls" command from grub's command prompt, it would 
be impossible to confirm how grub sees the usb port (i.e., whether it sees it 
as usb0 or as something else). The idea to create a custom grub entry to boot 
the iso directly from hard drive would be a much better bet, as the partition 
and path to file are not dependent on grub and would be known for sure.




On Thu, Aug 11, 2016, at 03:59 PM, Marcel Maci wrote:
> 
> Hello Bruno,
> Thx a lot for taking time to answer my question. I read about that (i.e. 
> using an existing system to install another one) today, but it seem's quite 
> complicated (and I'm not a pro). Actually, I discovered that there's a much 
> simpler way to do it:
> Even if grub does not show up, it is active (which means you just don't see 
> the entries). So when the system boots up you just press the down key of your 
> keyboard (which is also active) until the system get's to a halt (which means 
> that you are in the grub menu). From there you can directly select from the 
> standard entries:
> - u: to boot from usb
> - d: to boot from cd rom
> The problem then is that your installer will start in a low resolution 
> vga-mode (from what I understand) and you still won't see anything on the 
> screen. But if you know your distribution, you can blindly tap your way 
> through the first steps (in Trisquel it's just language selection and 
> choosing if you want to run live cd or install the system) until you finally 
> get to the graphical installer (and from there on it's no problem).
> I tried it with the CD today (and I suppose that USB should also work).
> Thx + greetings,
> Marcel
> 
> On Thu, 11 Aug 2016 15:24:44 -0400
> Bruno Dantas <address@hidden> wrote:
> 
> > > I have two more questions:
> > > 1) since grub doesn't show up - how can I boot from usb / cd?
> > 
> > Marcel,
> > 
> > Details greatly depend on the distro. Assuming you already have a distro 
> > installed on your machine, I think this could be your general strategy:
> > 
> > 1. On a machine where you can see the grub menu, tinker with a custom entry 
> > in /boot/grub/grub.cfg until you can successfully boot your usb
> > 
> > 2. On your libreboot machine, put that working custom entry in 
> > /boot/grub/grub.cfg and make it grub's default (either by making it the 
> > first menuentry or by editing /etc/default/grub as appropriate)
> > 
> > 3. Reboot your libreboot machine and it should boot your usb
> > 
> > 4. After you are done in the usb and before rebooting, mount the partition 
> > containing your installed distro and edit /boot/grub/grub.cfg so that your 
> > installed distro is once again the default
> > 
> > This worked for me for debian 8.5:
> > 
> > menuentry 'Debian usb' {
> >   linux (usb0)/live/vmlinuz boot=live
> >   initrd (usb0)/live/initrd.img
> > }
> > 
> > Configuration for booting some other distros from usb can be found here:
> > https://wiki.archlinux.org/index.php/Multiboot_USB_drive
> > 
> > -----------------------------
> > 
> > By the way, you don't even have to put the distro on a usb. Just having the 
> > iso on your hard drive is good enough. This works for me:
> > 
> > menuentry 'Debian iso' {
> >   set 
> > isofile='/home/bruno/Downloads/debian-live-8.3.0-amd64-mate-desktop.iso'
> >   loopback loop $isofile
> >   linux (loop)/live/vmlinuz boot=live config fromiso=/dev/sda4/$isofile
> >   initrd (loop)/live/initrd.img
> > }
> > 
> > Configurations for booting some other distros from iso can be found here:
> > http://www.howtogeek.com/196933/how-to-boot-linux-iso-images-directly-from-your-hard-drive/
> > http://git.marmotte.net/git/glim/tree/grub2
> > 
> 
> 
> -- 
> Marcel Maci
> Avenue du Guintzet 15
> 1700 Fribourg
> 079 772 50 30
> address@hidden
> www.liederlobby.ch
>