Below is a breakdown of what makes a PowerMTA config "hot," including a sanitized, high-performance sample file and an explanation of the critical directives that control the flow of data.
# ===================================================================== # PowerMTA Core Configuration for High-Volume ("Hot") Delivery # ===================================================================== # --- Global Settings --- host-name ://yourdomain.com daemon-user pmta daemon-group pmta # --- Logging & Accounting --- log-file /var/log/pmta/log status-file /var/log/pmta/status move-to /var/log/pmta/archive/ move-interval 1h records d,b,r record-fields d type,time,orcpt,srcIp,vmta,dsnStatus,dsnDiag record-fields b type,time,orcpt,srcIp,vmta,dsnStatus,dsnDiag record-fields r type,time,orcpt,srcIp,vmta,dsnStatus,dsnDiag # --- Performance & Resource Tuning --- max-msg-rate 50000/h max-smtp-out 2000 max-msg-per-connection 1000 bounce-retry-interval 15m max-retry-time 2d # --- Security & Access Control --- http-mgmt-port 8080 http-access 127.0.0.1 admin http-access 192.168.1.0/24 admin always-allow-relaying yes process-x-envid yes process-x-job yes always-allow-relaying yes log-connections no log-commands no # --- Inbound SMTP Settings --- smtp-listener 0.0.0.0:25 # --- Outbound Virtual MTA & IP Binding --- smtp-source-ip 192.0.2.10 host-name ://yourdomain.com smtp-source-ip 192.0.2.11 host-name ://yourdomain.com virtual-mta vmta-hot-01 virtual-mta vmta-hot-02 # ===================================================================== # Advanced Domain Directives for Major ISPs # ===================================================================== # --- Default Global Queue Rules --- max-smtp-out 20 max-msg-per-connection 100 max-errors-per-connection 10 retry-interval 20m # --- Gmail Specific Tuning --- max-smtp-out 100 max-msg-per-connection 200 max-msg-rate 500/m dkim-sign yes require-tls yes # --- Yahoo & AOL (Verizon Media) Specific Tuning --- max-smtp-out 50 max-msg-per-connection 50 max-msg-rate 200/m retry-interval 10m # --- Microsoft (Outlook, Hotmail) Specific Tuning --- max-smtp-out 40 max-msg-per-connection 30 max-msg-rate 150/m backoff-to-normal-after 30m Use code with caution. Critical Parameter Breakdown 1. Performance and Throughput Optimization sample powermta configuration file hot
postmaster postmaster@example.com host-name mailer.example.com log-level 2 max-smtp-out 5000 Below is a breakdown of what makes a
: Groups individual Virtual MTAs together. When your application injects mail into pool-hot-delivery , PowerMTA automatically distributes the volume across all listed IPs to prevent single-IP blacklisting. 3. ISP-Specific Traffic Shaping (Domain Directives) ISP-Specific Traffic Shaping (Domain Directives)