[SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

Flemur · 2012-05-25 14:56:01

Hi all -

This is my first shot at arch, tho I've installed a few other linux distros.

So far I really appreciate the excellent documentation, especially compared to other linuxes!

But I can't find a good answer to this question:

I already have ubuntu installed and would like to dual-boot with arch. (I also have Win7 but boot it from a separate disk selected via BIOS, and usually leave this disk disconnected anyway, so it's not an issue; grub doesn't know it exists).

Q: Before installing, can I make a new LOGICAL ext4 partition (say /dev/sda7),
- then install arch on that **w/o installing grub** and **without messing with the MBR**,
- then edit ubuntu's existing menu.lst to add arch to the boot options?

Current $ fdisk -l

/dev/sda1 ext4 primary/boot (/ for ubuntu)
/dev/sda2 extended
--/dev/sda6 linux-swap
--/dev/sda5 NTFS (data - mp3s, etc)
unallocated 480GB --> Create new ext4 partition /dev/sda7, (logical or primary? Prefer logical)

Current menu.lst entry that I normally boot:

title Ubuntu 12.04 LTS, kernel 3.2.0-24-generic REGULAR
uuid UUIDforSDA1 (file has actual UUID number...)
kernel /boot/vmlinuz-3.2.0-24-generic root=UUID=UUIDforSDA1 ro
initrd /boot/initrd.img-3.2.0-24-generic

and add something like this to menu.lst:

title Arch Linux
uuid UUIDforSDA7
kernel /boot/vmlinuz-linux root=/dev/sda7/ARCH ro (??? - from example in arch docs)
initrd /boot/initramfs-linux.img

or

kernel /boot/vmlinuz-linux root=UUID=UUIDforSDA7 ro (??? - like the ubuntu entry)

I'd really like to NOT mess up booting ubuntu! (Another option might be install arch to a separate disk with the ubuntu disk disconnected, then copy the whole install over via a USB adapter...I've done worse!)

TIA for any help!

Edit: so I guess there's three questions:
1 - Can I install arch w/o installing grub & MBR messing-wth?
2 - What's the correct syntax for menu.lst to access and boot arch?
3 - Will this work?

Last edited by Flemur (2012-05-25 15:24:18)

Inxsible · 2012-05-25 15:00:55

Flemur wrote:

Q: Before installing, can I make a new LOGICAL ext4 partition (say /dev/sda7),
- then install arch on that **w/o installing grub** and **without messing with the MBR**,
- then edit ubuntu's existing menu.lst to add arch to the boot options?

Yes. During the install simply skip the step to install Grub and everything should work. You will however, need to either manually edit your Ubuntu grub config to let it know about a new shiny Arch OS or you can even re-install Ubuntu grub since it can auto detect the operating systems installed. If you don't do this, you will not be able to log into Arch obviously.

Logical partitions are fine with Arch (for any linux actually) - In fact I have my entire arch (root, home, var, swap) in a logical partition.

Trilby · 2012-05-25 15:02:34

So are you asking whether you can use arch without installing a second copy of grub? Of course. That's the whole point of grub, you can have many OS's listed.

You ~~will likely~~may run into a problem however with the partitioning. AFAIK, at least to boot partition needs to be a primary (not extended) partition.

Edit: inxsible beat me to it, but there you have two votes.

Last edited by Trilby (2012-05-25 15:04:33)

Flemur · 2012-05-25 15:10:02

Thanks, I'm going to mark this SOLVED! (if I can figger out how...)

Inxsible · 2012-05-25 15:15:47

edit first post. Prepend title with [SOLVED]

oh and Welcome to the Arch forums.

Flemur · 2012-05-25 23:23:40

Well, it worked and booted up first time - no grub install.

The main hassle was merely creating a new ext4 partitions because "Partition Wizard" boot CD screwed up and I kept getting "Unable to update kernel until reboot" messages until I deleted and rebuilt all the partitions in the extended partition with puppy linux & gparted instead of Partition Wizard.

In case others stumble upon this trhread, here's some info:

The entry in the ubuntu (original) menu.lst was this:
title Arch Linux
uuid af7...etc...9f3c
kernel /boot/vmlinuz-linux root=UUID=af7...etc.f3c ro
initrd /boot/initramfs-linux.img

I'm even posting this from arch/fluxbox/Firefox, although getting X set up with nvidia (PITA!) apparently required using a different pacman source:

File "mirrorlist" now points to
Server = http://mirror.us.leaseweb.net/archlinux/$repo/os/$arch
which wasn't in the original file.

Then
$ pacman -Su --> "/etc/mtab exists" --> delete it and something else broke,
so
$ pacman -Su --force --> worked fine (against official advice)

Also: needed to install nvidia-utils and xorg-xinit

Thanks again!

Arch Linux

#1 2012-05-25 14:56:01

[SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

#2 2012-05-25 15:00:55

Re: [SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

#3 2012-05-25 15:02:34

Re: [SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

#4 2012-05-25 15:10:02

Re: [SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

#5 2012-05-25 15:15:47

Re: [SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

#6 2012-05-25 23:23:40

Re: [SOLVED] Dual boot with ubuntu w/o installing GRUB? (YES)

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