Sample Powermta Configuration File 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 }

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 sample powermta configuration file

# Custom throttles for ISP reputation domain-throttle hotmail.com max-msg-rate 10000/h max-conn 15 domain-throttle outlook.com max-msg-rate 10000/h max-conn 15 domain-throttle live.com max-msg-rate 8000/h max-conn 10 virtual-mta auth-domain default { bounce-domain bounce

virtual-mta bulk-low-priority smtp-service outbound source-ip 192.0.2.30 max-smtp-out 5 max-msg-rate 5000/h throttle-delay 100ms # Inject delay per message virtual-mta Outbound SMTP Service --------------------------- smtp-service outbound type outbound max-smtp-out 100 # Global cap across all vMTAs max-msg-rate 100000/h max-conn-per-domain 20 bounce-handler http://localhost:8080/bounce # HTTP bounce processor feedback-loop-handler http://localhost:8080/fbl use-starttls yes require-tls false dns-timeout 15s resolve-command /usr/bin/dig +short smtp-service --------------------------- Domain & ISP Specific Rules --------------------------- Fine-tune for major receivers to avoid rate limits and blacklisting. domain-mapping * { # Default for all domains max-smtp-out 10 max-msg-rate 10000/h max-conn-per-domain 5 throttle-startup 10 throttle-inc-interval 10s } sample powermta configuration file

# 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