The Admin Console provides the following two logging options:
Option 1 — Log stdout (System.out.print) content to the event log
Option 2 — Log stderr (System.err.print) content to the event log
When these options are set, stdout and stderr messages are written to the server.log file. (The event log is a syslog daemon on Solaris and Event Log on Microsoft Windows.)
If the above options are not set:
Anything written to stdout or stderr (that is, using System.out or System.err) will not appear in the logs.
Messages logged with the JDK logger will appear in the logs.
Messages written to stdout or stderr appear with the INFO level, but do not have a message ID.