View Full Version : [sendmail] "Smart" relay host

20th July 2004, 03:12 AM
Hi all,

First of all: I do *not* want to run the sendmail daemon!

I just want to use sendmail to push mail to the university's mailhub.
So I added this to sendmail.cf:

# "Smart" relay host (may be null)
But 'mail -v' seems to insist on the sendmail daemon running on localhost, as it produces this message:

pigpen@somewhere.de... Connecting to [] via relay...
pigpen@somewhere.de... Deferred: Connection refused by []

When I start the sendmail daemon by issuing "service sendmail start", the spooled mails get sent.
Question is: HOW do i get sendmail to use the relay host WITHOUT the sendmail daemon running.

20th July 2004, 03:19 AM
Sendmail still needs to run and listen on port 25. Mail uses it to pass the mail to sendmail, which then uses its rules for foreward/relay.

You can firewall all connections from port 25 except those from ( localhost )

20th July 2004, 08:43 AM
We have another machine (SuSE linux) which doesn't have any smtp daemon running:

Starting nmap V. 3.00 ( www.insecure.org/nmap/ )
Interesting ports on localhost (
(The 1595 ports scanned but not shown below are in state: closed)
Port State Service
22/tcp open ssh
80/tcp open http
139/tcp open netbios-ssn
443/tcp open https
3306/tcp open mysql
6000/tcp open X11

with the same "smart" relay host, mail functions as I desire. Any explanations?