Reported Issue
You get an exception similar to the one below when attempting to capture a backup with the dremio-admin command.
Exception: java.rmi.server.ExportException: Port already in use: 1099.
Relevant Versions
Reported on 25.0.0
Reproducible in 24.3.4
Other versions may also be affected.
Troubleshooting Steps
Check if JMX monitoring has been enabled in the cluster by going to $DREMIO_HOME/conf/dremio-env and validating if the parameters below have been added to the Java options:
-Dcom.sun.management.jmxremote.port=<monitoring port>
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.ssl=false
Cause
The cause of the issue is that the JMX parameters have been set in the wrong environmental variable. You've set your extra java options in the variable DREMIO_JAVA_EXTRA_OPTS while the variable you should be using is DREMIO_JAVA_SERVER_EXTRA_OPTS.
Steps to Resolve
Change the configuration to DREMIO_JAVA_SERVER_EXTRA_OPTS and this error will no longer happen. This configuration change will require a service restart.