Unanswered question

JBOSS monitor generates a connection refused (in the Neoload.log file)

When creating the JBOSS monitor config on the controller we get an error "Cannot connect to the service for an unknown reason. See logs for more information". This could be an authentication issue but we aren't sure. We get a different error if we try to connect to a server without the monitor so we're reasonably sure Neoload is finding the monitor and the 7200 port us open. The Neoload.log file includes a java exception "Error while connecting JMX engine java.rmi.ConnectException: Connection refused to host: FS101; nested exception is:
java.net.ConnectException: Connection refused: connect". NOTE the JBOSS server has three instances on separate JVMs so we have port offsets (8080 becomes 8180 etc)

Shane H.
Shane H.

Shane H.

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Answers

Nouredine A.
Nouredine A.

Nouredine A.

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4
5000 / 5000
points
Team

This issue might be related to a firewall. Do you have one installed on your JBOSS server?

In the documentation, in case of firewall, this is the port that needs to be opened. The port and files depends on your JBOSS version and configuration:

1099 (configurable through the Port attribute in the jboss-service.xml file)
- 1098 (configurable through the RmiPort attribute in the jboss-service.xml file)
- 4444 (configurable through the RmiObjectPort attribute in the jboss-service.xml file)

 

One more thing, if your monitoring agent is not installed on your JBOSS server, have you configured JBOSS to allow monitoring from remote machines?

You should check that as it can also be the root cause of your issue.

 

Shane H.
Shane H.

Shane H.

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22 / 100
points

The firewall is open to all traffic including the given ports and we've also confirmed through netstat that the required ports are listening on the JBOSS server. We don't have remote monitoring enabled however we are using a monitor installed on the JBOSS server itself which shouldn't require remote monitoring unless the controller also requires remote access.

Is there anything else we can check?

Nouredine A.
Nouredine A.

Nouredine A.

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4
5000 / 5000
points
Team

The controller does not need access to your monitored machine but only the agent does. Still the error message indicates that the connection to that host: FS101 is refused. So either the target port is not listening or the hostname does not point to the local machine.

Maybe you should check the /etc/hosts configuration file too in case you do not use DNS.

 

Shane H.
Shane H.

Shane H.

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0
22 / 100
points

We've successfully used the generic JMX monitor to connect as opposed to the JBoss monitor (JBoss v5.1) which still fails. How can we get the JBoss monitor connected? What info is needed to help diagnose the issue?

Nouredine A.
Nouredine A.

Nouredine A.

Level
4
5000 / 5000
points
Team

You have two different ways to configure JMX on a JBoss 5.x server. There's the standard JMX Mbeans Server and the JBoss embedded one.

JBoss 5.1 monitor is compatible with the JBoss embedded JMX server. You said that with the Generic JMX monitor it worked fine. Was it with  the JAVA URL?

If yes then it explains why it does not work with the JBoss 5.1 monitor. You probably configured JBoss with the JAVA JMX option on the start command. In that case, you can't use the NeoLoad JBoss monitor but only the Generic one.

You will be able to monitor the same kind of statistics but you will have to manually set your own threesholds and select the right counters suitable for your configuraiton.