Powermta Config File Link -

max-conn-rate : Limits the number of simultaneous connections to a specific domain like Gmail.

In a standard Linux installation (such as CentOS or Ubuntu), the primary configuration file is located at: /etc/pmta/config

The config file is typically split into several logical sections: Sets the global identity of the server.

Crucial for maintaining IP reputation by preventing "blasting" that triggers ISP spam filters. max-msg-rate : Limits messages per minute or hour.