I have searched and searched the forums and found none that were like my problem, I installed ubuntu to my external hd, which is compatible with everything, and installed the boot loader to /dev/sda3 which is the root partition on my hd which I wish to boot from, had a clean install with no errors, but now when I restart and get to the grub menu I get error 22, no such partition when I try to boot my ubuntu partition, I went into the details and such and found that it says root (hd0,1). What would I put there to get it to boot from the sda3 on which I installed the boot loader.

EDIT: I figured that out, after booting to the grub screen I went into the grub shell command line and typed, find /boot/grub/stage1 and it came up with (hd0,2). But will that pose a problem when I unplug my external hd, since lots of people have problems with that.

I assume you have installed ubuntu on one partition, sda3, on your usb drive and you do not have a separate /boot partition. If your / partition is on sda3, then it will be designated (hdx,2) in grub at boot time, with "x" being determined by grub usually, but not always, based on where sda is in your bios setup boot order. If you switch things around in your bios boot order or add/remove additional hard drives, that x could potentially change. It's not clear exactly what problems you anticipate from all this. Could you please expand.

I do not have a separate /boot partition, and I haven't changed my BIOS and probably won't, and the only thing changing about these hard drives will be the external might be unplugged. I don't really know how to expand on this besides that.

Do you have linux also installed on your internal hard drive with it's own version of grub installed to the hard drive mbr? If so, are you booting your usb install of ubuntu from this internal hard drive grub?

You said:

I'm trying to understand what kind of problems you are anticipating. If you have grub installed on your internal hard drive and are booting the usb install from that grub there could be issues if you remove the usb drive. If you are booting directly off the usb drive using the usb grub only, i.e. you're not chain loading the usb grub from the hd grub, I can't see how there could possibly be a problem.

I don't have grub saved in the MBR, and linux is all on the external hd, it boots fine and everything but I have to change where it thinks the root is from (hd1,2) to (hd0,2) every time.

Have you tried editing your /boot/grub/menu.lst file? That's the configuration file for grub. You would want to make sure root is designated (hd0,2) instead of (hd1,2) in menu.lst.

You confusing us all (and maybe yourself) with incomplete information.
- did you have another system installed prior to this ???
- which O/S, and which bootloader ???

If you installed to a partition you wouldn't even see a boot menu unless you chainload into it. Let's see a "fdisk -l" listing to get us going. For Ubuntu derivatives you'll need sudo; for Fedora it's /sbin/fdisk ...

Windows XP was/is installed on the internal, and I didn't write any grub thing on the mbr.

/dev/sda1 9641 34703 201318516 c W95 FAT32 (LBA)
/dev/sda2 2 122 971932+ 5 Extended
/dev/sda3 * 123 9640 76453335 83 Linux
/dev/sda4 34704 59766 201318547+ c W95 FAT32 (LBA)
/dev/sda5 2 122 971901 82 Linux swap / Solaris

Partition table entries are not in disk order


By the way, the FAT32 partitions are for storage for both windows and linux.