> On Nov 9, 2016, at 9:32 PM, vod vos <vod...@zoho.com> wrote:
>
> hi,
>
> when telnet mail.example.com 25 or 587, the server will echo 220,
>
> how to c_a_n_c_e_l the respond to telnet after mail server configuration?
Your question makes no sense...
An SMTP server will respond to TCP client connections via "telnet",
"netcat", "posttls-finger", "swaks", Perl scripts that connect to
port 25, Python scripts that connect to Port 25. Haskell programs
that connect to port 25... The server does not and need not know
the details of the client implementation.
That's the power of open standards like TCP/IP.
If you want to disable inbound email, turn off the smtp/inet service.
If you want to disable outbound submission, turn off the submission/inet
service.
--
Viktor.
