Exchange mass mailing?

Of course it is not recommended and there is much of cheap tools, but if your customer wants to send thousands of e-mails several times a day due to business needs and no delay is allowed, there is a possibility to set this behavior in Exchange:

The goal is to create special receive connector for this application and besides other settings you need (authentication, message size …) you should modify the following parameters:

  • MaxAcknowledgementDelay (Default 30 seconds) – This is time out parameter, if Exchange server cannot confirm delivery of message to all recipients, if the message was received by MTA, which does not support  shadow redundancy feature.
  • TarpitInterval (Default 5 seconds) – This parameter is valid for unauthenticated sources and specifies how much time SMTP response is delayed to source server in case, that Exchange determines source server is abusing connection.

The combination of settings MAxAcknowledgementDelay and TarpitInterval  to small values might put your environment to performance problems and it is NOT recommended to set it on internet receive connectors.


Get-ReceiveConnector SERVER\Relay | select *ack*,*tarp*,*lim*,iden* | fl

MaxAcknowledgementDelay : 00:00:30
TarpitInterval          : 00:00:05
MessageRateLimit        : Unlimited
Identity                : CHM2\Relay


Get-ReceiveConnector SERVER\Relay | Set-Receiveconnector -MaxAcknowledgementDelay : 00:00:01 -TarpitInterval 00:00:00

This will not work in Exchange 2013, since shadow redundancy has been improved and Safety Net feature has been added instead of transport dumpster..


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