> I think there might be some settings left from JOPR agent which cause this strange behavior of RHQ agent.
If you think that might be the cause, then you can restart the agent with the "--cleanconfig" argument. This will delete all of the agent's previously persisted configuration settings and data and it will ask you for the answers to the setup questions again. This will also force a re-read of the agent-configuration.xml file to pick up the settings found inside there.
If the clean agent doesn't solve the problem then check the agent.log file for messages like ""Unable to create oracle connection". Availability is marked UP/DOWN depending on whether the agent can not create a connection to Oracle. Perhaps you have too many connections at times...