I'm still testing everything out, this is a screenshot of Kibana 6.4 charting MySQL usage on 2 docker instances and one separate server, using Metricbeat 6.4 on each server (well, there is a single docker container monitoring both MySQL containers).
The docker instances combined do 6 reads every minute.
The standalone server does 10 inserts a minute every 5 minutes.
So, the connections rate, the opened tables rate, and the sent/received bytes rates don't seem remotely correct, especially when they oscillate into the negatives like they do.
This is what I'm seeing:
This is what I see when I look at the it running locally in VirtualBox (which seems a LOT more inline with what I would expect from the deployed instance)
The only thing I can think of (and this is just dawning on me), the Docker instances are running MariaDB latest, whereas the standalone server is running an old MySQL (version 5.7); could that old of a MySQL install be sending gibberish to Metricbeat?