Pmta - Configuration

Accepted connection from 127.0.0.1 DKIM signature verified for yourdomain.com Queue started: 10 messages active Delivered: 550c7e1f to gmail-smtp-in.l.google.com (250 2.0.0 OK)

First, she carved out the IP pools. She isolated the transactional emails—password resets, receipts—into a high-speed lane. These were the thoroughbreds. They needed pristine, dedicated IP addresses with strict throttling: max-smtp-out 20 per domain, throttle 5 per second. She gave them their own pool: ip 192.168.1.10-192.168.1.15 .

She opened the file. It was a cathedral of text—thousands of lines of directives, domain keys, DKIM selectors, and IP pools. It looked less like a config file and more like a spell book written by a paranoid genius. pmta configuration

<source 192.168.1.10/28> allow-mail-from *@yourdomain.com require-auth yes max-message-size 10M max-recipients 100 </source>

The mail server, Artemis , was dying.

The final step was the outbound access rules. She built a firewall in code:

<domain yourdomain.com> dkim-sign yes dkim-signature dkim._domainkey.yourdomain.com </domain> Accepted connection from 127

<bounce-domain *> bounces@bounces.yourdomain.com </bounce-domain>