[CentOS] Installing CentOS 6.2 *TO* a USB drive, not installing from USB.

[Emmanuel Noobadmin]

On 4/10/12, Patrick DERWAEL <patrick at derwael.be> wrote:
> Emmanuel,
> I used a totally different approach by using VMware: the trick is to
> install on a physical device which is the USB drive.
> When the installation requests a reboot, simply boot on your USB and off
> you go!

That is pretty much what I did. Boot DVD 1 with a USB DVD drive,
install to /dev/sda which is the USB flash drive. When the
installation requests a reboot, shutdown, remove as well as leave the
DVD drive around and reboot... and only grub prompt or Error 21.

Maybe there's a minor but critical step I'm missing so I'll appreciate
it if you could outline in greater details how you did it.

I've tried installing grub to both MBR i.e. /dev/sda as well as first
partition /dev/sda1 but neither works.