In a previous article I described how to install and run the Port Scan Attack Detector (PSAD) on a Raspberry Pi. It is the closest thing to a full IDS that works on the Raspberry Pi and it's extremely easy to set up.
None of the existing visualization tools for PSAD data really met my needs, so I created a custom Python script that generates an HTML page from the live PSAD data.
On my own host running PSAD, there is a cronjob that runs this script every five minutes and uploads the output to an AWS S3 bucket. If the local configuration or the settings on the AWS side would be useful to anyone, let me know!