On Wed, 11 Jan 2012, Leslie León Sinclair wrote:
I´m testing a server, so I need to unable people[users], to connect via telnet[smtp.mydomain.com:25] to the mail server.
If you're testing it, your best bet is to either a) bring it up as long as you need to test it, and then shut it down when you don't (ONLY for the purpose of testing), or b) set configuration to only allow mail from localhost - so this way, a user on the machine the server resides on could, in theory, type 'telnet localhost 25', but this assumes that the telnet client is installed thereon
Keep in mind, though, that there are people who keep the telnet client on machines that you don't have control of - and in my case, I keep it around to debug occasionally. You won't have control fo those machines, and direct telnet into a SMTP server is really not a security hole.
-Dennis
