Let's call the new service we are going to create 'probe.'
   Let's have probe run on port 999, which is unused.
   Let's make a batch file that probe runs called 'etcprobe.'
   Probe will be added with an entry in /etc/services.
   Probe will be started with an entry in /etc/inet/inetd.conf.
   Etcprobe will be stored in /usr/local/bin.

       /usr/local/bin/etcprobe
  +-------------------------------------------------------------------
  | #!/bin/sh
  | netstat -an | grep 999 | grep ESTAB | mail -s "Probe Alert!!" root
  |

        /etc/services
  +------------------------------
  |  ...
  |  ...
  |  probe     999/tcp
  |  ...

        /etc/inet/inetd.conf
  +----------------------------------------------------------------------
  | ...
  | probe   stream   tcp   nowait   root  /usr/local/bin/etcprobe   probe
  | 

Now apply the changes made to inetd.conf with the kill command. Test that probe is working by trying to telnet to port 999. You'll get mail to root in a few seconds.

<Jim.Van.Verth@>
gerberb@zenez.com