<domain att.net> route smtp.att.net:25 route backup-relay.att.net:25 weight=2 fallback-to-mx yes </domain>
This covers the essential domain-level configuration in PowerMTA. For a specific use case (e.g., Gmail, Yahoo, custom smart host), the route , max-smtp-out , and DKIM settings become most critical. powermta domain detail
PowerMTA (PMTA) treats domains as critical routing and policy endpoints. Unlike generic MTAs, PMTA separates the envelope domain (SMTP conversation) from the policy domain (rules). These are set within a <domain> block or global defaults. <domain> example.com ... Defines a specific domain configuration block. All settings inside apply only to this recipient domain. <domain att
<domain example.com> log-entries yes accounting-log /var/log/pmta/acct-example.csv </domain> Use pmta show domain commands: Unlike generic MTAs, PMTA separates the envelope domain
log-domain /var/log/pmta/domains/%d.log # %d expands to domain name Then within <domain> :
<virtual-mta domain-specific> bind-to-source-ip 192.168.1.100 <domain example.com> max-smtp-out 10 </domain> <domain gmail.com> max-smtp-out 20 route alt4.gmail-smtp-in.l.google.com:25 </domain> </virtual-mta> <domain yahoo.com> max-smtp-out 2 # total connections max-smtp-out-per-ip 1 # per destination IP smtp-pipeline-depth 5 # pipelined commands delivery-interval 10 # seconds between connection attempts 5. Routing & Failover Domains Smart host routing: