Arbitary Ports for JMX monitoring

FormerMember

I configured JMX monitors to monitor four JVM applications program in two servers, by adding following paramater after "java":

"-Dcom.sun.management.jmxremote.port=1090x -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false"

(where x is 1 to 4)

My first server places at the same network to my Solarwinds SAM server. So everything is OK.

However, my second server places at another network, which has a firewall between this server an Solarwinds SAM server.

I have allowed the JMX port, which specified at the java paramater.

I found that the JMX monitor is error with message "Cannot connect to JMX server".

After some troubleshooting, I observe from "netstat" that there are some arbitrary port used during JMX monitor polling:

So I have some questions about that:

1. What are those arbitrary ports for?

2. Can I avoid to open those ports?

3. Can I specify those ports number with java parameter?

aLTeReGo

1. What are those arbitrary ports for?

Each JVM will have it's own JMX port. If one is not specified via the command line or configuration file, then a random port will be automatically selected for use.

2. Can I avoid to open those ports?

There's really no way of avoiding these open ports if you want to agentlessly collect information from these JVMs remotely.

3. Can I specify those ports number with java parameter?

The port can be specified using the parameter "-Dcom.sun.management.jmxremote.port". E.G. "-Dcom.sun.management.jmxremote.port=1234"