[ubuntu-uk] boot from a external hard drive

[Rob Beard]

Rik Boland wrote:
> Hi
>
> I want to get started on Gento but I don't have another machine to work 
> with, nor do I want on, so is it all possible to use a external hard 
> drive in a caddy and to boot it up that way?
>
> I hope that makes sense and I hope you can.
>
> If you can how easy is it to do it?
>
> Shalom
>
>   
It should be possible, you'd need to make sure your BIOS can boot from a 
USB device (pretty much all machines built in the past 2 or 3 years can, 
possibly older ones too).  As a precaution I'd say backup anything 
important just in case.

When it comes to partitioning I would have thought your internal hard 
drive and your USB drive would come up as /dev/sdX (where X could be a, 
b, c etc).  You can find out what partitions are on the drives by 
running fdisk as root (or with sudo) with this command...

fdisk -l

I find it's easier if both drives are different sizes that way it's not 
as easy to get them mixed up (and it avoids accidentally deleting the 
wrong partition).

Another alternative to consider would be to run Gentoo in a virtual 
machine (maybe on Virtual Box or VMWare).  That way you can play with it 
whilst still being able to use Ubuntu.  Plus if you have a CPU which 
supports virtualization (Socket AM2 Athlon or higher, higher end Core 2 
Duo or higher - this will tell you which ones are supported 
http://en.wikipedia.org/wiki/X86_virtualization) then you can enable 
that in Virtual Box (IIRC it's under the option AMD-V or Intel-VT) and 
it will give near native speeds in the virtual machine.

It's worth bearing in mind too that Gentoo compiles stuff from source 
when it installs it.  I haven't looked at Gentoo in a couple of years 
and I believe they have a live graphical installer now but I'm fairly 
certain that it still needs to compile everything which can take some 
time (a few hours at least).  I'm not sure if you can now install a 
working system and then have it re-compile everything for the target CPU 
although it might be worth preparing for the possibility that you may 
not be able to do anything useable with your machine for a few hours to 
maybe a day.

Anyway hope this helps and good luck.

Rob