On 16 October 2012 17:14, Larry Martell larry.martell@gmail.com wrote:
On Tue, Oct 16, 2012 at 8:58 AM, Joseph Spenner joseph85750@yahoo.com wrote:
From: "m.roth@5-cent.us" m.roth@5-cent.us To: CentOS mailing list centos@centos.org Sent: Tuesday, October 16, 2012 7:49 AM Subject: Re: [CentOS] setting up postfix
Larry Martell wrote: This should be an easy one. I'm trying to get postfix going. I've never done this before. I followed the directions at http://wiki.centos.org/HowTos/postfix. I opened port 25:
iptables -I INPUT -p tcp -m tcp --dport 25 -j ACCEPT
But I don't receive the mail. In a file in /var/spool/postfix/defer I
see:
alt2.gmail-smtp-in.l.google.com[2607:f8b0:400d:c00::1a]:25: Network is unreachable
Have I missed a step or done something wrong?
Have you tested to see if tcp/25 is really open? From another system:
$ telnet ip.of.postfix.box 25
Do you get a sendmail/postfix message of some sort?
No, I can't connect:
# telnet 10.188.36.207 25 Connecting To 10.188.36.207...Could not open connection to the host, on port 25: Connect failed
iptables shows that port open:
Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT tcp -- anywhere anywhere tcp dpt:smtp
Chain OUTPUT (policy ACCEPT) target prot opt source destination ACCEPT tcp -- anywhere anywhere tcp dpt:smtp
Hi.
It seems you are telnetting using- and have firewall rules for- an IPv4 network. Your postfix seems to be trying to use IPv6. : alt2.gmail-smtp-in.l.google.com[2607:f8b0:400d:c00::1a]:25: Network is unreachable.
Does the client's network and ISP use IPv6?
Have you tried configuring inet_protocols = ipv4 in the main.cf ? Your box might be configured with IPv6, but that doesn't mean it is usable on the network.
OT: The default policies of your chains appear to be "ACCEPT" - thus if there is no REJECT or DROP rule matching your SMTP connection, it will be automatically accepted when it hits the bottom of the chain, regardless of what ACCEPT rules you apply.
Regards, Andy.