Not sure what you're trying to achieve or why 30 is your limit. Maybe you can elaborate?
Have you read the article about Session Management? https://docs.exasol.com/database_concepts/session_management.htm
your question puzzles me a little bit. In your last question you where asking about a Single Node VM Ware installation and now you are looking for a cluster setup. Can you DM me to see where the problem is? A Community Edition is not intended to work in a cluster. Let us help you there.
30 somehow rings a bell, but I don't remember what it exactly was. Probably the maximum recommended number of active sessions. But this shouldn't be a hard limit.
What's the result of this query in your system?
SELECT * FROM sys.EXA_METADATA em
WHERE PARAM_NAME IN ('maxConnections','maxStatements');