Postfix and iRedMail- Relaying Denied

postfixsmtp

I am trying to setup iRedMail and am way over my head here.
I have installed it, and can send emails internally, but not externally.
When I send an email from outside, I get the following return email:

The error that the other server returned was: 550 550 5.7.1    
<test@mailtest.domain.com.au>... Relaying denied (state 13).

Now I have no idea where to start looking! Any ideas?
I have really only just installed iRedMail so I am unsure what else I need to do to get it working.
I've pointed my MX records to that server, so that shouldnt be the problem.

Also- if i stop postfix (so nothing is listening on port 25) and send a test email, I get the same reply back. Why would I get the same reply back even if postfix is stopped? I have run tcpdump over 25 and can see the packets coming in/out, so its definitely a configuration issue!

I suppose my question is not really "what is my problem", but more "What configuration needs to be completed on postfix and iRedMail?"

Best Answer

So it is fixed, and it is quite a noobish mistake!

I should have twigged when i was getting the same error, even if port 25 was not open. Turns out.. I had an iptables rule in their that was forwarding to another server. So the relaying denied message I was getting was not even from the server i thought it was! Removing this rule has fixed the issue.

Related Solutions

Linux – How to correct Postfix’ ‘Relay Access Denied’

TLS just enables encryption on the smtp session and doesn't directly affect whether or not Postfix will be allowed to relay a message.

The relaying denied message occurs because the smtpd_recipient_restrictions rules was not matched. One of those conditions must be fulfilled to allow the message to go through:

smtpd_recipient_restrictions =
    permit_sasl_authenticated
    check_recipient_access hash:/etc/postfix/filtered_domains
    permit_mynetworks
    reject_unauth_destination

To explain those rules:

permit_sasl_authenticated

permits authenticated senders through SASL. This will be necessary to authenticate users outside of your network which are normally blocked.

check_recipient_access

This will cause postfix to look in /etc/postfix/filtered_domains for rules based on the recipient address. (Judging by the file name on the file name, it is probably just blocking specific domains... Check to see if gmail.com is listed in there?)

permit_mynetworks

This will permit hosts by IP address that match IP ranges specified in $mynetworks. In the main.cf you posted, $mynetworks was set to 127.0.0.1, so it will only relay emails generated by the server itself.

Based on that configuration, your mail client will need to use SMTP Authentication before being allowed to relay messages. I'm not sure what database SASL is using. That is specified in /usr/lib/sasl2/smtpd.conf Presumably it also uses the same database as your virtual mailboxes, so you should be able enable SMTP authentication in your mail client and be all set.

Centos – Sendmail – Relaying denied (state 14)

You probably don't have sendmail set up to accept mail for domain literals / IPs.

To see what sendmail has already discovered as a 'local' address, or what it thinks is local, do:

    echo '$=w' | sendmail -bt

And if you don't see your IP address in there, add it to /etc/mail/local-host-names:

    echo your.ip.addr.here >> /etc/mail/local-host-names

That should do it, given I've guessed the problem correctly from the info provided.

Best Answer

Related Solutions

Linux – How to correct Postfix’ ‘Relay Access Denied’

Centos – Sendmail – Relaying denied (state 14)

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