Zimbra - second domain stopped receiving mail

[SkyHiRider]

I've set up two domains on my server A.eu and B.com.
Both were working but after a day of use, the B domain stopped receivining mail.
Here's the message gmail returns when trying to send the mail:

Technical details of permanent failure:

Google tried to deliver your message, but it was rejected by the recipient domain. 
We recommend contacting the other email provider for further information about 
the cause of this error. The error that the other server returned was: 554 554 5.7.1 
<test@test.com>: Sender address rejected: Access denied (state 14).

I only have dnmasq set up for the A.eu domain.

[lytledd]

You should start by providing the relevant logs on the Zimbra side of things when the failure occurs.

/var/log/zimbra.log
/opt/zimbra/log/mailbox.log

Doug

[SkyHiRider]

Here are the logs:

[lytledd]

Your .eu domain is publicly pointing to your internal address of 192.168.77.87. In a split-domain environment, the Public DNS should point to a real world address and your internal DNS should be pointing to your 192.168 address. Search the forums for split-dns for a proper setup.

Doug

[SkyHiRider]

Thanks for the reply lytledd - I've noticed that yesterday and fixed it with my ISP.

The problem was that I had Bind configured for working behind a NAT and the ISP's DNS records used my LAN DNS as one of the nameservers, which probably means that my local DNS records were pushed outside the boundary of my LAN and were used instead.

That also explains why some mail (namely from clients in the LAN) went through.