Only upgrade security related packages:

Note

From iam-TJ at https://news.ycombinator.com/item?id=11475474

sudo /usr/bin/unattended-upgrade

Note

This will only use the ${dist}-security target. Most systems should have this installed and available. The default configuration is at: /etc/apt/apt.conf.d/50unattended-upgrades It is configured as a system service that runs automatically at shutdown.

Enable a service:

update-rc.d ssh enable

Import a gpg key into apt:

apt-key adv --keyserver pgp.mit.edu --recv-key KEY_STUFF

Find the Ubuntu version:

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 14.04.5 LTS
Release:        14.04
Codename:       trusty