Inbound Mail Problem SMTP / Edge to Exchange

[dimkyson]

Hi
i try to translate my german thread. it looks like nobody could help me in the german section.

Problem: I have a problem to transfer the incoming mail from dmz to lan. (See the attachment)

Edge / DMZ = 10.0.1.5
Exchange = 10.0.10.10
INT-DNS = internal DNS Server

Incoming Mail:
Internet -> DMZ Edge Mailrelay / Mailforwarder -> Exchange Server = all emails stay in queue on DMZ Mailrelay with error "451 4.4.0 DNS query failed"

telnet exchange 25 = OK.
telnet exchange 587 = Ok.

Outgoing Mail:
Exchange -> DMZ Edge Mailrelay / Mailforwarder -> internet = all mails arrive @recipient / Ok.

Rules: @ETH1

Proto   SRC   Port   Dest         Port   GW
UDP     *      *     Int-DNS      53      *
TCP     *      *     Exchange    25      *
TCP     *      *     Exchange    587     *
TCP    DMZ   *     *               25      WAN1
TCP    DMZ   *     *               587     WAN1

Someone an idea? If you need more information about the rules or something pls post…

Thanks for your help...

if you want reply in german: http://forum.pfsense.org/index.php/topic,57002.0.html

[podilarius]

How is the exchange server listed In the mail forwarder? If you put in the ip instead of a name, does the mail flow as expected?

[dimkyson]

atm i'm in xmas holidays. I will try to change this option… Do you think the DMZ Server is unable to resolve the the hostname? i write down my experience asap...

Thanks for the fast reply.. merry xmas

[podilarius]

just a guess. the rules seems to be okay. there is probably not any routing problems, so long as everything if using the pfense as its gateway.

[dimkyson]

I didn't foud the problem. I solved my problem by installing pfsense 2.0.2 on a different Dell Server with different hardware. That is not really a solution!