APMIA Cassandra extension is unable to get metrics from Cassandra with the following messages
[IntroscopeAgent.JMXClient] No Mbeans found that match the filter criteria
[IntroscopeAgent.JMXClient] Access Denied
DX APM SaaS
The Cassandra extension is using the remote jmx access to access Cassandra, so the key is to make sure the remote jmx password file (jmxremote.password) is accessible for the user and contains the user/password.
Please refer to the Cassandra doc on jmx access for more details: