postfix timeout sending to exchange 2003

Posted on 2005-04-13
Last Modified: 2012-06-27
I am diagnosing a problem where a single sender's domain returns an NDR to the sender when they email to a recipient on Exchange 2003 server.  The Recipient server running Exchange 2003 does not exhibit any unusual behavior receiving from other domains.   The sender is able to deliver mail to other Exchange 2003 recipient servers without difficulty.

Recipient firewall is configured to permit sender's IP address range via SMTP (without any IDS running on this address range), and to permit inbound SMTP from sender's IP withour restriction.

The sender receives a 4.0.0 timeout from their ISPs postfix server after 8 hours.  Specifically:

Reporting-MTA: dns;
X-Postfix-Queue-ID: 6808E3D00FE
X-Postfix-Sender: rfc822; user@senderdomain.local
Arrival-Date: Wed, 13 Apr 2005 09:24:24 -0400 (EDT)

Final-Recipient: rfc822; user@recipientdomain.local
Action: failed
Status: 4.0.0
Diagnostic-Code: X-Postfix; connect to mail.recipientdomain.local[]:
    Connection timed out

Final-Recipient: rfc822; user2@recipientdomain.local
Action: failed
Status: 4.0.0
Diagnostic-Code: X-Postfix; connect to mail.recipientdomain.local[]:
    Connection timed out

I suspect some sort of Postfix/Exchange 2003 incompatibility, but can't say for sure what the details of the postfix server configuration might be.  Any ideas?


Question by:vtsinc
    LVL 8

    Accepted Solution

    Try upping your timeout settings:

    In add:

    smtp_helo_timeout = 300s
    smtp_connect_timeout = 300s


    postfix reload

    And keep a close eye on your logs.

    LVL 6

    Author Comment

    Thanks for the tip.  The problem actually turns out to be an incorrect ingress filter on an upstream ISP's network, but since you were the only responder and your information could easily have been related to fixing the problem under other circumstances I think it is appropriate to award the points.


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