Today i got the following error when i was trying to start 12C OMS, the error message was found in emctl log file location in <12c_install_home>/gc_inst/em/EMGC_OMS1/sysman/log/emctl.log, below was the error message :-
2015-12-30 14:41:24,136 [Thread-1] INFO wls.OMSController run.1744 - <OUT>Jython scans all the jar files it can find at first startup. Depending on the system, this process may take a few minutes to complete, and WLST may not return a prompt right away.
2015-12-30 14:41:24,136 [Thread-1] INFO wls.OMSController run.1744 - <OUT>
2015-12-30 14:41:24,771 [Thread-2] INFO wls.OMSController run.1744 - <ERR>*sys-package-mgr*: can't create package cache dir, '/tmpWLSTTemporacle/packages'
2015-12-30 14:41:45,764 [Thread-2] INFO wls.OMSController run.1744 - <ERR>java.io.IOException: Permission denied
# Interestingly the solution was to change the /tmp directory permission to 755 and make sure /tmp is readable and writeable. Sometimes what happens the permissions on tmp directory changes , and there is a 'Permission denied' message when trying to create the 'Packages' directory for the package cache directory. In this case the directory is "/tmp/WLSTTemporacle' but could also be /tmp/wlstTemp or /var/tmp/wlstTemp depending on Platform. Regardless of the platform the solution is the same i mentioned above.