RMI executor could not be started - cant load workflow into memory - started service still issues

RMI executor could not be started, see log file for details

at com.knime.explorer.server.rest.RestServerExplorerFileStore.throwCoreException(RestServerExplorerFileStore.java:403)
at com.knime.explorer.server.rest.RestServerExplorerFileStore.loadWorkflow(RestServerExplorerFileStore.java:1319)
at com.knime.explorer.server.internal.view.actions.rest.RestServerExecuteAction.execute(RestServerExecuteAction.java:251)
at com.knime.explorer.server.internal.view.actions.rest.RestServerExecuteAction.access$1(RestServerExecuteAction.java:245)
at com.knime.explorer.server.internal.view.actions.rest.RestServerExecuteAction$2.run(RestServerExecuteAction.java:155)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:56)
Caused by: java.lang.RuntimeException: An error occurred during the creation of a job for ‘/FILE_send_mail/VCPL (Vivrity) COLLECTIONS REPORT’: RMI executor could not be started, see log file for details

at com.knime.explorer.server.rest.RestServerContent.createWorkflowJob(RestServerContent.java:1850)
at com.knime.explorer.server.rest.RestServerExplorerFileStore.loadWorkflow(RestServerExplorerFileStore.java:1311)
... 4 more

link for log file -

There’s several problems apparent from the log files:

ERROR : KNIME-ConfigurationArea-Checker :  : ConfigurationAreaChecker :  :  : Configuration area ("/opt/knime/knime_4.0.1/configuration") seems to be used by a different process, found file lock on "org.knime.core/root.lock" (used by user root). This may lead to undesired effects in multi-user setups, see KNIME FAQs: https://www.knime.com/faq#q34.

This means that permissions of the executor got messed up. Also it indicates that you are running the server as root which you should not do.!

2020-01-29 14:40:10,429 : ERROR : main :  : KNIMEExecutorApplication :  :  : Requested RMI port 50109 is already in use, exiting.
java.rmi.server.ExportException: Port already in use: 50109; nested exception is:

This means that there is another process already using the port designated for the executor. This could be the same process that is also holding the lock from the above error.

thanks @thor for reply.

from the beginning am using with root user.
I will check with permission.

How can i start executer?
i mean any solution for this -
KNIMEExecutorApplication : : : Requested RMI port 50109 is already in use, exiting.
java.rmi.server.ExportException: Port already in use: 50109

The executor starts automatically, if it finds a free port to use for communication with the KNIME Server. But apparently all free ports are already used. Find out which processes use those ports (on Linux with netstat) and shut them down. If you cannot shut them down, configure a different port range for the executor in knime-server.config.

can you please look into this…

which is not usefull ?

I checked all permission , all are good ,

what different port range i can use ?

after i killed 8080 port no PID…
then i reboot the system
then i checked - ```
sudo netstat -plten |grep java

It seems this problem is caused by the recent Java update to 8u242 on Ubuntu. The only workaround at the moment is to downgrade to a previous Java version, e.g. 8u232. We are working on a fix.

thanks for info… @thor
it will be great if you can help me with java downgrade ?

any other solution on this ?

See Java update 8u242 breaks execution with RMI executors

Thanks, @thor -
you are a savior.

after downgrading , it works fine.

1 Like

I have downgraded the java , it works fine
but after 2 days updates installed again , again server stopped working.
again i downgrade java version.

Any solution on this ?

Until we have released the bugfix, disable automated updates.
My personal recommendation is to disable them in any case. In 99% of all cases they are fine but in the remaining 1% an update my break something (see the current problem) and then nobody is there to fix it in time if it happens e.g. Friday night. Therefore internally we always apply updates semi-automated. There is always someone at the computer triggering the update and checking whether everything still works. If not, the updates can immediately rolled back.