Using jconsole with authentication 

How to use jconsole with authentication.

After configuring JMX authentication, using jconsole requires a username and password to complete the remote connection to the Cassandra cluster. Use an appropriate username/password combination.

Procedure

Start jconsole using a pre-configured JMX username and password for <username> and <password>:

For Cassandra 3.6 and later, the username and password can be an internally configured Cassandra role and password.