[SOLVED] issue receiving mail - problem with name resolution

[mfehr]

I created a fresh setup of Zimbra 5.0.5 on a fresh installed Ubuntu 6.06 behind an ipcop firewall.

When receiving e-mails, the e-mail is received and virus checked fine. The next step the logfile shows is postfix/lmtp ... deferred ... connection refused. The reason is that the name resolution is done for the external IP address of my MX record.

Tests I did to check the configuration:
mail.xxx.com is configured in /etc/hosts as well as on the internal DNS server pointing to my internal IP address
My mail MX record points to mail.xxx.com: host -x mx xxx.com confirms mail.xxx.com
ping mail.xxx.com talks to my internal IP address
/etc/resolv.conf shows my internal DNS as the first DNS

Nevertheless the mail delivery catches the external IP address for my mail server rather the internal one. Any hints?

[phoenix]

If you're behind a NAT router you need a Split DNS set-up and a correct /etc/hosts file. You need to post some information showing your DNS resolves OK & the hosts file is correct

[Bill Brock]

When a mail client/server delivers to another mail server, it checks DNS for the MX record with the lowest serial number. Then it checks for the A record that resolves to the MX record.

It is the delivering mail server which determines which IP to deliver to by the info it receives from it DNS querry. The receiving mail server can be made to listen on a specific IP but other than that it has nothing to do with which IP a sending server or client uses.

[mfehr]

Thanks. Installing and configuring bind9 on my zimbra host (ubuntu 6.06 server) solved the problem. Now zimbra got it's own dedicated DNS server.