Best products from r/Splunk
We found 1 comment on r/Splunk discussing the most recommended products. We ran sentiment analysis on each of these comments to determine how redditors feel about different products. We found 1 product and ranked them based on the amount of positive reactions they received. Here are the top 20.
https://smile.amazon.com/gp/product/1593275099/
I am not sure about the size of your environment. If it's small, Splunk may be way outside your budget.
Take a look at that link above if you really want to build an open source solution for security monitoring. It'll take a lot of elbow grease and knowledge of your business to be effective. Pick up the book and build yourself a POC to see what you can see.