The TCP/IP port number on which this server waits for a shutdown
command. Set to
-1 to disable the shutdown port.
Note: Disabling the shutdown port works well when Tomcat is started
using Apache Commons Daemon
(running as a service on Windows or with jsvc on un*xes). It cannot be
used when running Tomcat with the standard shell scripts though, as it
will prevent shutdown.bat|.sh and catalina.bat|.sh from stopping it