Recommended and mentioned products
Splunk's operational intelligence platform helps unearth intelligent insights from machine data.
You need a free account on splunk.com to download the software; it looks like they've changed the site some, but what you want is here, that's the download page for "Splunk Enterprise" (not Splunk cloud).
Snort is a free and open source network intrusion prevention system.
Take a look at the snort 3 ubuntu installation guide on snort.org (I'm the author), it walks you through getting Snort 3 and Splunk working together well.