I have OpsCenter 5.0.2 running on a node, and Cassandra 2.1.2 and the Agent 5.0.2 running on another node. I installed both OpsCenter and the Agent using yum/rpm on CentOS 7.
I have no problem using OpsCenter with this agent when I run the Agent's binary directly. However, when I run the datastax-agent service, OpsCenter never sees the connection. Attempting to install the agent from OpsCenter never worked (I always received a "lost connection" error).
I've looked at startup.log and everything looks normal: it loads the confiuration and starts Jetty. agent.log also looks normal: it says it has connected to the cluster, gets to Using partitioner: Murmur3 and that's the end of it. I'm not sure if the logs should say more at this point.
I've also looked for any errors in journalctl as well as systemctl status and don't see anything of interest.
Any ideas on where else to look?