Does anyone can help me what I should check my mail server I just installed on RH9. I am using sendmail 8.12.8, everything were just fine except to send out to Internet address. I can send msg out locally without problem, but if I send msg to Internet, it shows connection timed out in my mailq status. Below is the exact error msg I captured from mailq:

/var/spool/mqueue (1 request)
-----Q-ID----- --Size-- -----Q-Time----- ------------Sender/Recipient-----------
j6M0o5xB010941 696 Thu Jul 21 20:50 <abc@abc.org>
(Deferred: Connection timed out with gsmtp171.google.com.)
<XYZ@gmail.com>
Total requests: 1


I checked my mail server is able to connect Internet and I also tried to send mail msg from Internet to my mail server, it works OK, too! I can receive mail from Internet. But I cannot send out!

Any idea?? Thanks!

You have to tell sendmail to listen on the network. Change in the sendmail.mc file in /etc/mail
Comment out the line with dnl
dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
Then you must rebuild sendmail.mc
Many ways to do, make works on some systems

I checked my sendmail.mc file, and I've already changed to listen 0.0.0.0 instead of 127.0.0.1. Here I captured from my conf file

DAEMON_OPTIONS(`Port=smtp,Addr=0.0.0.0, Name=MTA')dnl

if even I comment out, the problem is still the same. What else I can check?