External Hard drive

I am thinking of dual booting Linux with windows 7 but would I be able to install Linux straight onto an external hard drive and boot from that? If not would I be able to use it in both partitions or will it need reformatting? Thanks, Kyle

As long as your BIOS supports booting from USB hard drives (most do nowadays) then yes you’ll be able to install it on an external drive and boot directly to it.

My advice would be to disconnect your current (Win7) hard drive whilst installing Linux to the external drive… once it’s installed and working, reconnect your Win7 drive, and use the BIOS to choose which drive to boot from. (most BIOS’s will offer you a list of devices to boot from when you press the F10 or F12 key as you boot)

If you leave the Win7 drive connected during the install, the Linux bootloader (GRUB) will overwrite the Windows bootloader, and depending on where you install GRUB, you may not be able to boot Windows without the external drive being attached.

Thanks, how would i go about unpluggging the win7 drive? I’m on a laptop btw. Also are there any guides on how to install onto my external hard drive?

You will have to visit your laptop manufacturers website to find out how to remove the hard drive.
(or give us the make and model, and we’ll try to find instructions for you)

Once it’s removed you won’t need a guide that’s specifically written for external drives… as it will be the only drive, so any installation guide will be ok.

Be Aware - removing your internal hard drive may affect your guarantee… check first.

This can be done without removing the internal drive first, but then there is a risk of messing up windows… the risk is small but has to be mentioned.

Oh, and don’t remove the drive with the laptop switched on… best to have it unplugged, and the battery removed whilst removing the internal hard drive. (may seem obvious, but you’d be surprised what some people do :wink: )

Thanks for the help, I’ll try this tomorrow and let you know if i have any other questions :slight_smile:

Just a thought.
What if you ran a live session from the DVD, then Admin - Disk Utility and unmount the hard drive then try to install. Surely it should try and install on the only available drive which is your external drive.
As I say only a thought, as I am only a newbie myself. Maybe the experts on here will know better. ???

There’s still the chance stage 1 of the GRUB bootloader being installed to the MBR of the first hard drive (unless you know what you’re doing)… as the other parts of grub would then be installed to the external drive… the external drive would then need to be attached to boot either OS.

I was attempting to keep them completely separate, with a bootloader on each drive.

Point Taken.

Just one of those things normally learned by screwing up your system… guess how I learned :wink:

For more info on how grub works and where the different stages normally reside:

As you’ll see…
Stage 1 is installed to the MBR of the primary boot device… it then passes control to stage 1.5 or 2
Stage 2 normally resides on the Linux drive/partition, and part of its job is to display the boot menu

So if stage 1 ended up on the Windows drives MBR (overwriting the Windows one), but stage 2 was on the external Linux drive… unless the external drive was attached grub would drop to a command line.

And then neither OS would be easily bootable.

Yes… you could make the external drive the primary boot device without disconnecting it, but to save mistakes…
:wink:

Also, mounting is akin to attaching to the file system… booting from a LiveCD doesn’t automatically mount the harddrive/partitions anyway, yet GRUB can still be installed to the MBR, so either the installer mounts it or the MBR isn’t considered a normal part of the file system and is permanently available for writing… if you see what I mean.

Like I said… just trying to remove scope for a semi-disaster :slight_smile:

You will be able to install Linux directly on an external hard drive and boot from it. You can also use your internal hard drive. To internal hard drive you should install Linux in different partition from the windows 7. And You should have good memory space for the installing the linux.