Sample Powermta Configuration File May 2026

domain-mapping yahoo.com { max-smtp-out 8 max-msg-rate 5000/h max-conn-per-domain 4 use-starttls yes require-tls false rcpt-to-nxdomain-limit 3 }

# 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 sample powermta configuration file

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 } domain-mapping yahoo