snip
>
>
> Is there a way to partition the drive in a running system?
>
> The only way that I know of is to reboot onto a rescue disk and
> use gparted there to partition the drive.
>
snip

You can use parted on running systems just fine. On older systems, the
drive with the OS will not update the partition table until you
reboot, but repartitioning other drives should be updated fine. Parted
will warn you if a reboot is needed.

On newer systems, even the drive under the running OS can be updated
without a reboot.

I installed gparted using CLI.
I can find a preferences file for gparted (that won't open) but I cannot run the
program. I tried using a number of techniques to start gparted but so far nothing
is working. I am not worried about doing a reboot to a rescue disk and then doing
the work and then rebooting back into Debian testing but am also trying to use
this as a learning opportunity (hopefully without that being learning how to redo
the system as a whole which I have had to do at least twice since the original
install).

Thanks for your advice!

Dee