To verify that a service is listening on a specified port number, use the cstool utility ping command. Pinging a service does not verify that a service is actually running but indicates if it can accept a socket connection.
The Calendar Server service options are:
HTTP Service (cshttpd)
Administration Service (csadmind)
Event Notification Service (enpd)
You cannot ping the DWP service (csdwpd), or Notification Service (csnotifyd).
For example, to ping the machine with the host name calserver to see if the cshttpd service is listening on port 80:
cstool -p 80 -h calserver ping http
By default, cstool waits 120 seconds for a response; however, you can change by value by using the -t timeout option.
For the complete utility reference material, refer to Appendix D, Calendar Server Command-Line Utilities Reference.
To run cstool, Calendar Server must be running.