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Juan Largo
September 27th, 2011, 07:46 PM
I've been using Linux for about 5 years and it is my main operating system. I have a question that I can't find the answer to. Before you tell me to RTFM, let me assure you that I have searched these forums, done a thorough Google search, and read through the GRUB2 manual.

Here's the question:

How do I include the cheat code "VGA=789" when booting with GRUB2?

I need that cheat code to prevent a loss of signal to my monitor while I boot Kubuntu 10.04.3. Otherwise, my monitor shuts off. I can add the cheat code when booting the Live CD, but I don't know how to include the cheat code after I install Kubuntu on the HDD.

With legacy GRUB, all I had to do is open menu.lst in a text editor, type in the cheat code on the boot line, and save the file. With GRUB2, menu.lst is gone and from what I've read, I'll have to write some sort of computer program in order to make any changes to GRUB2.

Please don't give me the usual responses about how much better GRUB2 is compared to classic grub, or how I must learn an esoteric computer language in order to keep up with everybody else. I'm not a computer programmer, and I'm too old (67 years) and don't have the time or patience for writing elaborate scripts to do simple things like this. I just want it to add a simple boot code without having to get a college degree in computer programming.

If you can help an old guy like me, thank you in advance. If you can't offer help, please refrain from posting comments.

Yours truly,

Juan Largo

matt_symes
September 27th, 2011, 08:16 PM
Hi

You need to add it to the grub command line ? If that is the case then open a terminal.

Type


sudo nano /etc/default/grub

to start nano editing the grub file.
Enter your password. It will not be echoed to the screen. This is normal.

Scroll to the line that looks something like


GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

and change it to


GRUB_CMDLINE_LINUX_DEFAULT="quiet splash VGA=789"

Press ctrl and o at the same time to save and ctrl and x to exit nano.

After that type


sudo update-grub

When grub has been updated, reboot.

Kind regards

Juan Largo
September 27th, 2011, 08:43 PM
@ matt_symes

Thank you very much for your help.

I would need to run the commands you posted from the Live CD in the rescue mode, because without "VGA=789" boot code already included, my monitor would be off (no signal). So this brings up another question: How do I run the final command "sudo update-grub" from the Live CD in order to update GRUB on the HDD?

I have one final question:

If I use the "VGA=789" cheat code with the Live CD when I install Kubuntu, would the installer carry the cheat code over to GRUB2 in the final installation? If it does, then my problem is solved.

MAFoElffen
September 27th, 2011, 09:09 PM
@ matt_symes

Thank you very much for your help.

I would need to run the commands you posted from the Live CD in the rescue mode, because without "VGA=789" boot code already included, my monitor would be off (no signal). So this brings up another question: How do I run the final command "sudo update-grub" from the Live CD in order to update GRUB on the HDD?

I have one final question:

If I use the "VGA=789" cheat code with the Live CD when I install Kubuntu, would the installer carry the cheat code over to GRUB2 in the final installation? If it does, then my problem is solved.
You have 2 options:

Option 1:
Bring up Grub Boot menu by repeated pressing the shift button while booting... At the Grub boot menu, press "e" to put it into an edit mode. Arrow down to the line starting with "linux" which is the kernel boot line, go to where is says "ro quiet splash" and add your "vga=789" kernel boot switch. Press <cntrl><x> to boot. Make the changes in /etc/default/grub to make it persistent.

Option 2:
Boot from LiveCD. Mount your system usiing the chroot instructions in the second half of post #3 (http://ubuntuforums.org/showpost.php?p=10740097&postcount=3) of my stcky. Those instructions were for mounting a sys and installing drivers, but can be used for grub also... Set #5 for you would be:


gksudo gedit /etc/default/

Make you changes adding your kernel boot switch, then
[code]
sudo update-grub
[code]
Refer to posts 1-3 for reference and instructions:
Sticky: [all variants] Graphics Resolution- Upgrade /Blank Screen after reboot (http://ubuntuforums.org/showthread.php?t=1743535)

MAFoElffen
September 27th, 2011, 09:14 PM
I have one final question:

If I use the "VGA=789" cheat code with the Live CD when I install Kubuntu, would the installer carry the cheat code over to GRUB2 in the final installation? If it does, then my problem is solved.
Wait. it's not installed yet?

Follow the instructions on the first half of post 3 of my sticky to change the boot options of the LiveCD... The install routine "will not" carry over the "kernel boot option" (not referred as a cheat code") to Grub during the install...

So you will still need to make it persistent using the instructions I gavee you in the last post.

Juan Largo
September 27th, 2011, 10:05 PM
Wait. it's not installed yet?

Follow the instructions on the first half of post 3 of my sticky to change the boot options of the LiveCD... The install routine "will not" carry over the "kernel boot option" (not referred as a cheat code") to Grub during the install...

So you will still need to make it persistent using the instructions I gavee you in the last post.
You are correct. I have not installed Kubuntu yet; however, I know that I'll need to include "VGA=789" in order to get a signal to my monitor, so I'm planning ahead.

I understand your instructions. Option #1 (hitting the Shift key repeatedly) will allow me to add the cheat code that permits me to boot into Kubuntu. Then I can use the instructions posted by you and matt_symes to modify GRUB2 after booting from the HDD.

Option #2 (using chroot to modify GRUB2 from the Live CD) would also work, but I think it would be a little easier to do it using Option #1.

Thank you for pointing out that the cheat code entered on the Live CD will not stick in the final installation. So I know I'll have some work cut out for me in order to complete the installation.

I believe the problem is solved. Now I just need to get to work.

Thanks a million for your help.

btw - I like Kubuntu very much and I look forward to making it my primary operating system.

Yours truly,

Juan Largo

mörgæs
September 27th, 2011, 11:59 PM
Good. If the problem is solved, please mark the thread so using 'thread tools'.

oldfred
September 28th, 2011, 07:52 PM
With grub2 VGA= is obsolete.

vga=xxx is a deprecated boot option
Use this with your monitor size in /etc/default/grub:
GRUB_GFXMODE=1024x768
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/454993
"VGA Deprecated" Message on Boot
http://ubuntuforums.org/showthread.php?t=1453524

VGA conversions if you do not know mode:
http://wiki.archlinux.org/index.php/Gensplash
http://wiki.antlinux.com/pmwiki.php?n=HowTos.VgaModes