Grub 2 Basics

[peter b]

probably this, below, would help

http://ubuntufriends.wordpress.com/2...-the-easy-way/

[hgurol]

Alright, this is what worked for me.

1- I have created an bootable Grub2 iso file...

grub-mkrescue --output=rescue.iso /boot/grub

http://members.iinet.net/~herman546/...l#GRUB2_CD-ROM


2- Using one of the Iso editing software I have altered the "grub.cfg" file. You can use Iso Master on Ubuntu (thx Peter) or UltraIso on windows, or whatever your choice of utility to edit the files inside the Iso image without altering its structure and bootable status.

I used a very simple and basic "grub.cfg" file sample and edited it to my needs and according to my setup.
http://grub.enbug.org/grub.cfg


3- Now the most important part, where I have wasted too much time myself. Which "grub.cfg" file needs to be altered inside the iso?

In the Iso image structure there is one at the root of the image "/" and one another on the "boot/grub/i386-pc/" path. The answer is "None" of them. You dont edit those "grub.cfg" files but you place a new one on the path of "boot/grub/"

Thats about it...

[drs305]

3- Now the most important part, where I have wasted too much time myself. Which "grub.conf" file needs to be altered inside the iso?
Thats about it...

Is it grub.conf or grub.cfg, which is the normal configuration file for Grub 2? If the latter, just edit your previous post rather than make a correction in a new one.

[altima]

hello!

how do you make linux with grub2 boot with the option acpi_sleep=old_ordering?

I mean I could write it into the Grub menu.lst, but I don't know where to write it in the grub2 settings.

and without this line my PC is not able to suspend/hibernate normally.

thanks in advance!

[drs305]

hello!

how do you make linux with grub2 boot with the option acpi_sleep=old_ordering?

I mean I could write it into the Grub menu.lst, but I don't know where to write it in the grub2 settings.

and without this line my PC is not able to suspend/hibernate normally.

thanks in advance!

That would be added to end of the following line in /etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_sleep=old_ordering"

After saving the file, run "sudo update-grub"

[altima]

thank you so much! it helped and I got the idea =)

[mhenriday]

Normally you d onot need to edit that file at all. I would check to make sure that it looks like this;

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0

I lest that top line there to show where that is in the file. If that # is not there you will have a hidden menu.

I am hoping that you edited that out of your post. It should be in your /etc/default/grub file either commented (as above) or uncommented.

If it is not there I would put it in and if you have success booting in I would remove grub-pc and grub-common (the real problem here if that is not in there) and then reinstall them

...

Thanks again, ranchhand, for your response ! A problem - perhaps the problem ? - is that I find myself unable to comment the line «GRUB_TIMEOUT=5» ; I have no problem inserting a «#», but I can't save it. When I try, I'm asked what the file is to be called and where it is to be saved. If I they attempt to save it under, e g, the «Files» folder with the name «/etc/default/grub», I see the following error message

Could not save contents
Error opening file '/etc/default/grub': Permission denied

As a matter of fact, I can't do any editing at all, nor are commands of the type

grub-mkconfig

carried out ; instead the following appears in my terminal :

/usr/sbin/grub--probe: error: cannot find a device for / (is /dev mounted?).

The above seems to have to do with the fact that I'm running the terminal from the Lucid Live CD rather than a version installed to my harddisk. Previously, as noted above, one could use the Live CD to recover GRUB, but hitherto all my attempts to do so with GRUB2 have failed. I've done a backup of my most important files to an external harddisk, but I'd really rather avoid having to re-install the OS....

Henri

[drs305]

The above seems to have to do with the fact that I'm running the terminal from the Lucid Live CD rather than a version installed to my harddisk. Previously, as noted above, one could use the Live CD to recover GRUB, but hitherto all my attempts to do so with GRUB2 have failed. I've done a backup of my most important files to an external harddisk, but I'd really rather avoid having to re-install the OS....

Henri

Henri,

It sounds like you are either not running as root or did not "chroot" successfully. If you are trying to reinstall Grub2, follow the procedures here (as RanchHand linked).
https://help.ubuntu.com/community/Gr...0from%20LiveCD

If you continue to have problems, I would suggest starting a thread of your own, describe the problem, and then run and post the results of the boot info script found here:
http://bootinfoscript.sourceforge.net/

More people will be likely to look at a new thread, and RanchHand will no doubt find it. I'll continue to watch for it as well if the above doesn't fix things.

[mhenriday]

Drs305, thanks for your suggestion ! I doubt, however, that the problem is a failure to run as root - as can be seen from my post on p 46 of this thread, entering

sudo chroot /mnt

in a terminal results in

root@ubuntu:/#

which I interpret to mean that the manoeuvre has been successful. But it is not my intention to kidnap this thread, so I'll start a new one and see if what happens....

Henri

[drs305]

Drs305, thanks for your suggestion ! I doubt, however, that the problem is a failure to run as root - as can be seen from my post on p 46 of this thread, entering

sudo chroot /mnt

in a terminal results inwhich I interpret to mean that the manoeuvre has been successful. But it is not my intention to kidnap this thread, so I'll start a new one and see if what happens....

Henri

Yes, if you were getting the "root@ubuntu:/# " then you should have been operating as root. I'll watch for your new thread.