post/dovecot

willcastle · 09-21-2010, 07:23 PM

HI,

our company is running postfix and dovecot as mail servers on centOS. the outgoing mail has no problem but we cannot receive any mails.

i have no idea if its a firewall issue, a misconfigured mail server.

thank you and God bless.

alunduil · 09-21-2010, 07:26 PM

Can you provide more details as to the nature of the problem? What do the log files say? Where does mail stop getting delivered. Have you checked the three way handshake and the MX records?

Regards,

Alunduil

willcastle · 09-21-2010, 07:34 PM

honestly sir i have no idea where to start. in mxtool.com when doing port scan it says that the ports 110 and 25 are closed. only port 80 is open.

willcastle · 09-21-2010, 07:36 PM

in ms outlook 2003 we can send email to anywhere and has no error, but we cannot receive any incoming mails.

alunduil · 09-21-2010, 07:42 PM

What kind of firewall do you have in front of the postfix service? To check for iptables you can use: `iptables -vL` but if it's a hardware firewall you'll have to talk to your hosting company about how to modify the hardware firewall.

Out of curiosity, which hosting provider do you use?

Regards,

Alunduil

willcastle · 09-21-2010, 07:46 PM

our firewall is pfsense 1.2.3-RC1. is iptables the default firewall of cent0S?

willcastle · 09-21-2010, 07:49 PM

Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination

This is the output sir.

alunduil · 09-21-2010, 09:09 PM

There isn't really a default firewall of CentOS but it does ship with iptables. Is port 25 blocked by your pfsense firewall?

willcastle · 09-21-2010, 09:20 PM

it is in the NAT of pfsense, along with the pop3 and the email servers IP.

alunduil · 09-21-2010, 09:31 PM

I don't understand what you mean. pfsense is a NATing firewall that maps to a private IP on the server?

Regards,

Alunduil

willcastle · 09-21-2010, 09:42 PM

Yes, I think so.

krishnakant · 09-21-2010, 09:44 PM

As per my understanding first you check mail server iptable status . If it is running then you first stop it and check you mails. If iptables not running your server then need to open port
in your firewall. You also analysis your log files and hope you understand your problem.

Best of Luck..

willcastle · 09-21-2010, 09:49 PM

Applying iptables firewall rules: iptables-restore: line 3 failed
[FAILED]
This is the result of stop/start iptables.

Where do I locate the iptables?

Thanks

alunduil · 09-22-2010, 08:33 AM

The iptables rules are stored in /etc/sysconfig but if you're not using iptables you want to simply leave it off and make sure chkconfig lists it as off as well.

Regards,

Alunduil

Noway2 · 09-22-2010, 11:47 AM

If ports 110 and 25 are closed it is also possible that the applications that run on them (postfix and dovecot) are not running. What is the output of:

Code:

 netstat aux | grep postfix and netstat aux | grep dovecot

Does it show the daemon processes or just you grepping for them?

If they aren't running, try telling them to restart and check the processes again. Then look at your syslog to see if you get any sort of error message that tells you what is going on. Of course, this is all assuming that the problem isn't caused by your firewall.