the Free Edition is limited to 3 sessions, so it’s likely you are getting that error if you run multiple Kafka streams against the database, while querying it.
to get the F1 test demo running (I guess it’s the one of @randyzwitch), I think you are thinking to use Immerse to visualize data from the database, so you would ask for a temporary Enterprise license following this link
after you get the new licence, you should rename the file where the license is old (omnisci.licence) that’s located into the omnisci’s data dir (default is /var/lib/omnisci/data/), restart the server and, enter the new licence when prompted from Immerse,
If you aren’t going to use Immerse or features like BE Rendering, you could use the OS edition of the software, but you would remove the actual installation before installing the Open Source Edition. The installation process if similar to the one you used for the Free Edition, and you can get the step from here.
Or you can use just 1 Kakfa stream querying the database with another session and setting the idle-session-duration to 1 to be sure that that idle session are close ASAP, but I ì’m not sure it’s possible to run the full F1 Demo.
Hopes this helps,