Queued Mail 4

[porterno]

Over the past weekend, I brought up an Exchange 2K3 server (running on W2K3 OS) and since then the message queue has been slowly building. Intially (within the first 12 hours) it jumped to about 150 message queues and since then it has steadily risen to about 250 to 300. When I look at the messages themselves, most if not all are "Delivery Status Notification Failures" with postmaster@mydomain.com as the sender and random email addresses as the recipient. My initial reaction, was that I was being used as an open relay but after further investigation and testing (ORDB.org) I confirmed that I'm not. Is this type of queuing normal? Is there something I'm missing? Any suggestions or ideas would be most helpful. Thanks in advance.

 

[pkirill]

From another Exchange 2003 newbie, this same thing happens to us. When spam is sent to an non-GAL member (ie 12QWX45@domain.com), Exchange tries to send an NDR. Since most of the reply info provided by spam is invalid, the NDR can't go anywhere. So it stays in a queue while it attempts it's retries. This is a simplified explanation and I'm sure someone with more experience can provide a better one. To help combat it, I adjusted our time-to-rety and time-to-fail to 2 and 12 hours respectively (down from 12 and 48, I think?).

I also found a VB script that dumps the BADMAIL folder and that has helped...

 

[7139]

Another way is also to disallow NDR's to the internet. GLobal Settings>Internet Message Format>properties of the defaul (or other if any others have been created)Advanced and untick Allow Non Delivery Reports.

 

[PhillyCheeseSteak]

Porterno,

As 7139 noted, disable the NDRs that your system is attempting to send out to spammers who are using fake email addresses. All systems today should disable NDRs to prevent clogging of their servers when messages bounce.

-Phil