Ubuntu 9.10

dreamweaver547 · 11-08-2009, 03:21 PM

I was wondering if anyone's had any experience of editing GRUB 2 (version 1.97-beta4)?

Have managed to change

Code:

GRUB_TIME_OUT=-1

to give myself a chance to select an operating system, but am looking to edit the boot order and later on (maybe) install a new o/s. In the earlier version of grub the order was changed from

Code:

/boot/grub/menu.lst

But now it's not recommended to change anything in

Code:

boot/grub/grub.cfg

, so am I stuck with this boot order?

If I installed another linux operating system what is the procedure for updating in this version of GRUB?

Thanks

tom4everitt · 11-08-2009, 04:10 PM

This guide is probably what you're looking for, it explains most of the basic differences between grub 1 and 2:

https://wiki.ubuntu.com/Grub2

I believe you can change the os order (I think its explained how to in the guide).

In short grub.cfg is auto generated from some other configuration files, which you can edit. Exactly what and where you can change stuff is in the guide.

widget · 11-09-2009, 01:18 PM

There is a lot of good info in this link;

http://ubuntuforums.org/showthread.php?t=1305113

It is a brief intro but the links are great. The first 3 are particularly useful.

dreamweaver547 · 11-09-2009, 01:37 PM

This is nowhere near as simple as the previous GRUB version where I just cut and paste the order from /boot/grub/menu.lst

All I'm looking to do is to change the display order to make Ubuntu first and XP second followed by memtest and everything else, and I'm dubious about cutting and pasting anything.

Can't seem to get clarity from this documentation unless I'm missing something somewhere...

widget · 11-09-2009, 02:02 PM

The right way to do this would be to cut and paste your entries from /boot/grub/grub.cfg to /etc/grub.d/40_custom in this form;

Code:

echo "Adding Main on sda6 (2.6.24-24-generic)" >&2 
cat << EOF
menuentry "Main, kernel 2.6.24-24-generic (sda6)" {
	set root=(hd0,6)
	search --no-floppy --fs-uuid --set e2e3cd65-bc09-487f-be96-a83fcc282e38
	linux /boot/vmlinuz-2.6.24-24-generic root=UUID=e2e3cd65-bc09-487f-be96-a83fcc282e38 ro quiet vga=773
	initrd /boot/initrd.img-2.6.24-24-generic
}
EOF

that is an entry for hardy.

For my grub2 using OS' I use;

Code:

echo "Adding Lounge on sda7" >&2 
cat << EOF
menuentry "Lounge on sda7" {
    set root=(hd0,7)
        linux /vmlinuz root=/dev/sda7 so quiet splash
        initrd /initrd.img
}
EOF

that is a great entry. It never needs updated. It works if you change the OS from 9.04 to 9.10 (or in this case 10.04testing).

If you cut paste the info from your /boot/grub/grub.cfg it needs the;

Code:

echo "Adding Lounge on sda7" >&2 
cat << EOF

before the entry and;

Code:

EOF

after it. Make sure you get the last } in the right place.

Should look something like this;

Code:

echo "Adding Stoned-Lizard1.0 on sda8" >&2 
cat << EOF
menuentry "Ubuntu, Linux 2.6.32-2-generic" {
        recordfail=1
        if [ -n ${have_grubenv} ]; then save_env recordfail; fi
	set quiet=1
	insmod ext2
	set root=(hd0,8)
	search --no-floppy --fs-uuid --set 97dd103f-06ce-4aa8-a3aa-307ad432c355
	linux	/boot/vmlinuz-2.6.32-2-generic root=UUID=97dd103f-06ce-4aa8-a3aa-307ad432c355 ro   quiet splash
	initrd	/boot/initrd.img-2.6.32-2-generic
}
EOF

When you get your file built, save it as 06_custom and then it will be at the top of your menu on the screen.

You will need to run;

Code:

sudo update-grub

This will over write your /boot/grub/grub.cfg file and impliment the changes. That is how it is done.

If this is to much. Check the link to the intro I gave you before. Somewhere toward the bottom of the link listed there in, is one about something like "if grub2 is too much". It will guide you to have grub-legacy. Follow the directions, there are pitfalls you do NOT want to deal with.

Remember that grub-legacy (0.97) is no longer supported.

dreamweaver547 · 11-10-2009, 01:24 PM

Thanks - I will run a test on this at some point on another pc and if it works, will do this on my main pc.

widget · 11-10-2009, 02:54 PM

Well, I can't fault you for caution at all.

That said, the worst that will happen is that the custom entries will not work. The rest of the menu will still be there in the same way it is now.

When I first installed Ubuntu, I broke it 5 times in 7 days by too much playing with it. That is when I started down the path to multi boot. I dual booted Hardy/Hardy and did nothing on the "main" install with out trying it in my "play" install. So I really do understand where you are coming from.