[SOLVED] sendmail stop listenning on port 25

limdel · 09-19-2013, 04:46 AM

Hi,

After a fresh installation of CentOS (i386-minimal), i had installed sendmail to setup this box as SMTP gateway.

After basic setup,the command sendmail is able send email using:

Code:

cat email.txt | sendmail mymailbox@mydomain.com

However after restart service sendmail, the MTA deamon is listenning on port 127.0.0.1:25 for a few second:

Code:

# netstat -plnt |grep :25
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      1197/sendmail

But after it's stop listenning at all.

on /etc/mail/sendmail.mc i have comment the default limitation

Code:

#DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

The firewall is setup as:

Code:

# iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:smtp
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED
ACCEPT     icmp --  anywhere             anywhere
ACCEPT     all  --  anywhere             anywhere
ACCEPT     tcp  --  anywhere             anywhere            state NEW tcp dpt:ssh
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

And the strange thing is the log file

Code:

# tail /var/log/maillog
Sep 19 16:02:11 centostest sendmail[1622]: daemon MTA: problem creating SMTP socket
Sep 19 16:02:11 centostest sendmail[1622]: NOQUEUE: SYSERR(root): opendaemonsocket: daemon MTA: server SMTP socket wedged: exiting

"daemon MTA: server SMTP socket wedged: exiting", how can i troubleshoot this ? why the deamon would exit so quickly ? a conflict ?

Can anyone bring some light to my dark day ?
Any advise are welcome.

Thanks

bathory · 09-19-2013, 06:06 AM

Quote:

But after it's stop listenning at all.

on /etc/mail/sendmail.mc i have comment the default limitation
Code:

#DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

Use the following (add a dnl) to comment out the line:

Code:

dnl #DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl

Or you can comment out both lines above, so sendmail listens on port 25 on all available interfaces.

limdel · 09-19-2013, 09:28 PM

@bathory
Thanks for the reply, you put me on the right direction.

The fact is that i didn't read carefully the "manual", shame on me !

I just notice that to comment a line in the sendmail.mc file we had to use the "dnl" not "#"

Now it's ok with this:

Code:

dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl

Once again, thanks