I've not attempted this, but you could try changing the logging level of the logging.properties file from INFO to something like FINE or DEBUG. The file is located in the C:\Program Files\ArcGIS\Portal\framework\runtime\jre\lib directory. Look for the following section toward the top of the file:# Default global logging level. # This specifies which kinds of events are logged across # all loggers. For any given facility this global level # can be overriden by a facility specific level # Note that the ConsoleHandler also has a separate level # setting to limit messages printed to the console. .level= INFO
Once you re-save your file, try to start your Portal service and then review the service_error.log file (the same one you provided entries for earlier) and see if more helpful information shows up.