<domain aol.com> max-smtp-out 10 max-msg-rate 100/h </domain> DKIM Signing <domain example.com> dkim-sign yes dkim-selector myselector dkim-key-file /etc/pmta/dkim/example.com.pem </domain> Generate DKIM key:
pmta show queue pmta show stats pmta show vmta pmta show connections pmta show smtp-sessions Control sending across multiple dimensions: powermta configuration guide
pmta check config # Validate syntax pmta reload # Graceful reload pmta restart # Full restart tail -f /var/log/pmta/pmta.log PowerMTA is powerful but requires careful tuning. Start with conservative throttles, monitor bounce logs, adjust domain stanzas based on ISP feedback, and use virtual MTAs to separate traffic types. Always test with low volume first, especially for new IPs/domains. <domain aol
<source 0.0.0.0/0> auth-user myuser mypass require-auth yes </source> Better: restrict injection to localhost or a specific internal IP. Use domain stanzas to tune retries, timeouts, and throttling per recipient domain. <source 0
<virtual-mta transactional> vmta-name transactional source-ip 192.0.2.10 max-smtp-out 50 max-msg-rate 10000/h queue-type FIFO </virtual-mta> <virtual-mta marketing> vmta-name marketing source-ip 192.0.2.20 max-smtp-out 200 max-msg-rate 50000/h queue-type FIFO </virtual-mta>
<limit-group bulk> max-smtp-out 100 max-msg-rate 10000/h max-bandwidth 10M </limit-group> <virtual-mta marketing> limit-group bulk </virtual-mta>