Powermta Configuration File - Sample

# Require authentication for relaying auth-require true auth-scheme LOGIN auth-source file /etc/pmta/auth.db

# Optional: listen on multiple interfaces interface 0.0.0.0 max-message-size 50M log-connections yes log-session no dns-timeout 10s idle-timeout 300s max-recipients 1000 max-failures 20 soft-bounce-limit 5 slow-start yes slow-start-initial 10 slow-start-max 100 slow-start-period 30s smtp-service Virtual MTA (vMTA) Definitions --------------------------- Each vMTA can have separate IP pools, throttles, and sending profiles. virtual-mta hotmail-pool smtp-service outbound source-ip 192.0.2.10 192.0.2.11 192.0.2.12 # Rotate source IPs max-smtp-out 30 max-msg-rate 20000/h # Soft throttle max-msg-rate-per-connection 10 connect-timeout 30s idle-timeout 60s use-starttls yes require-tls false dns-timeout 10s sample powermta configuration file

auth-domain default { bounce-domain bounce.local bounce-address bounces@bounce.local } Bounce & Feedback Loop Processing --------------------------- bounce-processing { process-bounces yes bounce-return-top 50 # Include up to 50 original headers detect-loop yes max-bounce-rate 10% # If >10% bounce, throttle sending bounce-suppression 7d # Suppress addresses bouncing for 7 days } sample powermta configuration file

(For High-Volume Production Email Delivery) # ------------------------------------------------------------------- # PowerMTA Configuration File - Sample for High-Volume Email Delivery # ------------------------------------------------------------------- # Version: 4.5+ # Purpose: Production-ready configuration with deliverability tuning # Notes: Adjust paths, IPs, domains, and resources to your environment. # ------------------------------------------------------------------- --------------------------- Global Process Directives --------------------------- process-id-file /var/run/powermta/pmta.pid spool-directory /var/spool/pmta log-directory /var/log/pmta max-smtp-out 100 # Max concurrent outbound connections (all MTAs) max-errors-per-domain 10 # Failures before marking domain dead max-errors-per-recipient 3 domain-error-expiration 30m # Retry dead domain after 30 minutes recipient-error-expiration 30m --------------------------- SMTP Service (Inbound) --------------------------- smtp-service port 25 access-source config # Use IP-based rules below access-rule allow 127.0.0.1 access-rule allow 192.168.1.0/24 access-rule deny all sample powermta configuration file

domain-mapping aol.com { max-smtp-out 6 max-msg-rate 4000/h max-conn-per-domain 3 idle-timeout 120s }

domain-mapping *.edu { max-smtp-out 2 max-msg-rate 500/h throttle-delay 200ms } DKIM Signing --------------------------- dkim-sign domain example.com selector1 dkim-keyfile /etc/pmta/dkim/example.com/selector1.pem dkim-identity @example.com dkim-headers From:To:Subject:Date:Message-ID dkim-signature-expiration 7d dkim-sign

virtual-mta gmail-pool smtp-service outbound source-ip 192.0.2.20 192.0.2.21 max-smtp-out 20 max-msg-rate 15000/h connect-timeout 45s use-starttls yes require-tls true domain-throttle gmail.com max-msg-rate 12000/h max-conn 12 virtual-mta