Look at your output from the fdisk -l command above. It shows sda as a 160GB drive. Is that your internal drive? It also shows sdb as a 500GB drive. Is that your external drive? You have Linux partitions on sda1 and sdb5 which in Grub would be (hd0,0) and (hd1,4) respectively. You ran the commands below to install Grub to the mbr and have it pointing to (hd0,0) which is sda1 and is the Ubuntu you are now able to boot, right?

sudo grub
root (hd0,0)
setup (hd0)
quit

Look at your menu.lst posting. Toward the bottom you will see this line:

Just below that line you will see the following:

The entries below that are for an "existing installation" so the menu.lst you have posted is the second one you installed which should be the external.

Did you run the commands I suggested in earlier post "sudo mkdir /mnt/sdb5...? Did you get any errors when you did this? If you did not get any errors or have any problems with the commands, you should be in the external menu.lst. I don't know what else you may have done but if you put the entry I suggested in the internal drive Ubuntu /boot/grub/menu.lst file and it is not right, the external just won't boot and we'll try something else.

Also, I didn't mean "quit", if you look at your menu.lst file, what I posted is just a title entry I copied from it.

Also, if you want to have just Ubuntu on the external drive and have it be able to boot when set to first boot priority on another computer, you will then need to put Grub in the mbr of the external drive. Not sure how you want to do this??

Ok I did it. And it works smootley

Thanks everyone for all the help!

So that everyne understands: when my ext is plugged in I still boot my internal automaticly. But when I press escape I can choose. And thats just what I wanted.

But I'm not yet able to boot froma windows pc. how can I change that?

Thanks!

Are you talking about connecting your external hard drive to another windows only pc to boot the external with Linux/Ubuntu? As I indicated in my last post, if you want to be able to do that, you will need to install Grub stage1 to the mbr of that external hard drive. Then when you connect it to another computer, you will have to have whatever drive number your external drive is set first in boot priority on that machine.

Exactly what I'm talking about. So how do I install grub stage 1 to mbr? But I allready know how to make my disk the primary boot.

Boot into the Linux partition which contains the copy of grub that you want to use. Log in as root (or use sudo) and issue the grub-install command. See:

man grub-install

--------------------
Steve Stites

Ok, i did the command, but it doesn't tell me how to install grub to the mbr. So could someone please tell me how?

Thanks!

If you haven't made any changes since the last post to your bootloader, you should be able to install Grub to the mbr of the external by booting into the Ubuntu on the external and issuing commands:

sudo grub
root (hd1,4)
setup (hd1)
quit

Thanks alot,
That was all I needed:-)