I would like to set some Ubuntu Server VM's to always pull updates (nightly) with out asking?
Have a look at cron-apt
There is an article here that will tell you how to disable the update pop-up.
You then need to run
apt-get update apt-get -y upgrade
from root's crontab
i wouldn't recommend unattended updates, but you can do something like this:
create a file...
update.sh for example, throw it in
#!/bin/sh apt-get update apt-get -y dist-upgrade
chmod 700 /usr/local/sbin/update.sh and
chown root.root /usr/local/sbin/update.sh
then in root's crontab, add a line:
15 03 * * * /usr/local/sbin/update.sh
this will kick off your
apt-get update and
apt-get -y dist-upgrade every night at 3:15am
15 03 * * * /usr/sbin/apt-get update && /usr/sbin/apt-get -y dist-upgrade
in root's crontab
sudo crontab -e to edit it.
if you want to download only:
15 03 * * * /usr/sbin/apt-get update && /usr/sbin/apt-get -yd dist-upgrade