This is a quick blog post to demonstrate the Security Onion Upgrade Script. If you're running Security Onion 20110101 or newer, you can download and run the Security Onion Upgrade script to do an in-place upgrade. In the screenshot below, you can see that I started with Security Onion 20110116 and then ran the following commands:
sudo bash security-onion-upgrade.sh
The upgrade script then upgraded the system to 20110117 and then to 20110118.