How to stop mail relay 1

[PhilMarshall]

I have sendmail running on my servers, but I only need it to send mail out from processes running on that machine. I have no need to send mail out from any other machine. How can I prevent any other machine from sending mail using these servers?

 

[Masi]

You should have a line in the configuration module witch is
"Enable ralay control". Enabling that you let your server manage only the mail to or from the authenticated clients.
Witch are the local processes, clients logged in by a telnet server, and so on.

i hope that helped!
Masi