topic regarging smtp in Operating System - Linux

regarging smtp

Uma Maheswar — Sun, 29 Jul 2007 18:29:54 GMT

Hi,

I am trying to configure sendmail, when I do telnet localhost 25 its goes through, I do telnte example.com 25, the domain is able to resolve . I am able to do telnet example.com but I con't telnet example.com 25 what could be the reson and How I can trouble shoot.

Thanks

Uma Maheswar

Re: regarging smtp

Ivan Ferreira — Sun, 29 Jul 2007 19:22:18 GMT

1- Configuration, check sendmail.mc and verify that DAEMON_OPTIONS is commented, like this:

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

the "dnl" keyword is used to comment a line in sendmail configuration macro files. Recreate the configuration file:

m4 sendmail.mc > sendmail.cf

Restart the service

2- Firewall:

service iptables stop
Or
system-config-security

3- Selinux?
setenforce 0

Re: regarging smtp

skt_skt — Mon, 30 Jul 2007 22:26:28 GMT

here is what i did when i was not able to connect to port 25 or use smtp

sendmail.cf file coming with RH7.2 only listens on loopback interface. u can see that in netstat -an

it looks like this

tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN

I Commented following option and restarted the sendmail daemon.

O DaemonPortOptions=Port=smtp,Addr=127.0.0.1, Name=MTA

Then after restarting the daemon using netstat -an.
the output changed to

tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN

My mail now works