Slow SMTP Relay for Applications using Exchange 2010 Receive Connectors.
In this post we will look at the default “SMTP Delay” for messages received from a system that don’t support shadow redundancy. By default, Receive connectors delay acknowledgement up to 30 seconds.
For more information, see “Delayed Acknowledgement” in Understanding Shadow Redundancy.
To view the current “MaxAcknowledgementDelay” on a receive connector run the following on Exchange Shell.
Lets go ahead and change this value to have no delay.
This example sets the maximum acknowledgement delay to zero on the Receive connector External Relay Receive Connector.
Run the following command.
Set-ReceiveConnector "External Relay" -MaxAcknowledgementDelay 0
After setting the “MaxAcknowledgementDelay” 0 ,this is what the connector looks like.