--On 10. september 2005 11:02 +0100 Paul Howarth <paul@xxxxxxxxxxxx> wrote:
On Sat, 2005-09-10 at 11:48 +0200, Sasa Stupar wrote:
Hi!
I am running Sendmail 8.13.4 on FC4 with cyrus2. I have configured
sendmail to listen on ports 25 and 587. Since all of the client mail
software use port 25 by default instead of 587, how do I make users to
use 587 and deny access to 25? Something like: when they try to connect
to port 25, they get back error - you are not a server so you must use
port 587.
Where are these users located?
You can turn off relaying for everywhere except localhost, which will
give any non-local clients a "relaying denied" error; using port 587
they will need to authenticate and that will override the relay check.
You can't easily tell the different between an MUA and an MTA connecting
to your port 25 - they are both acting as SMTP clients. This is why port
25 blocking became necessary in the first place.
Paul.
--
Paul Howarth <paul@xxxxxxxxxxxx>
Maybe this should be the next step in evolution of the mail servers - to
recognize MUA and MTA correctly. This is only my thinking.
Regards,
Sasa
