<virtual-mta client-b> smtp-source-host 203.0.113.20 mail.client-b.com # Syntax: domain-key <selector>,<domain>,<private-key-file> domain-key s1,client-b.com,/etc/pmta/dkim/client-b.key <domain *> # Sign all outbound mail add-sign-header true </domain> </virtual-mta> Modern PowerMTA setups often use the HTTP API for better throughput and easier integration than SMTP. Dfx Music Player Enhancer Pro 1.30 7
<smtp-listener 0.0.0.0:25> # Allow relaying only from specific IPs (your web servers) allow-relay 192.168.1.10 require-auth true </smtp-listener> If your application writes emails to a directory instead of sending via SMTP, use the pick-up directive. Kilohearts Disperser Crack Apr 2026
<domain *> # Standard retry schedule retry-after 10m
# Backoff Configuration # If we see these errors, slow down backoff-notify Postmaster@yourdomain.com # Specific ISP Backoff rules # Example: Hotmail/Gmail often require slower sending on new IPs backoff-max-msg-rate 10/m backoff-retry-after 1h backoff-start 500 </domain> Always configure backoff to notify you. If an ISP throttles you, you need to know about it immediately to investigate content or list hygiene issues. 5. Authentication and Security (DKIM/SPF) While SPF is set in your DNS records, DKIM must be configured within PowerMTA to sign outgoing emails. DKIM Signing You must generate keys and point PowerMTA to them. This is typically done inside a VirtualMTA block.