NetBay journal
15 practical Email articles from Netbay Engineering — written for operators running Linux and Windows VPS in India.
15 articles in this topic
Master the art of self-hosting a reliable email server by validating PTR reverse DNS records, configuring feedback loops, and executing a staged IP warmup plan.
Stop spambots and brute-force scanners before they reach Postfix queue processes by deploying Postscreen pre-greeting tests and SpamAssassin scoring.
Safely advance your domain's DMARC policy from p=none to p=reject without dropping legitimate transactional emails using automated RUA report analysis.
Implement OpenDKIM cryptographic signature verification on Postfix with automated 2048-bit key rotation and dual-milter pipeline integration.
Configure a rock-solid Postfix outbound SMTP relay with Cyrus SASL authentication, opportunistic-to-mandatory TLS, and per-domain outbound rate limits.
A single-domain Postfix plus Dovecot inbox is small and honest: IMAP for you, DNS auth in place, and no claim that Gmail will accept your outbound.
A 10/10 mail-tester score is not inbox placement. Read Authentication-Results, the Received chain, and spam headers on a real Gmail or Outlook copy.
Hard bounces must suppress the address. Soft bounces may retry with a cap. Infinite queues hurt IP reputation and hide dead users in your app.
Pick the sending path by daily volume, bounce work, and whether users must read the message. Direct VPS SMTP only wins at tiny, well-authenticated mail.
Keep local sendmail and cron working, but hand the public hop to SES, Mailgun, or Postmark. Postfix sasl_passwd and smtp_tls are the whole design.
Start DMARC at p=none, read aggregate reports, then raise to quarantine and reject once every legitimate sender aligns. Do not skip the report week.
DKIM survives forwarding when SPF does not. Sign with OpenDKIM on Postfix, publish a 2048-bit TXT key, and verify the signature on a received copy.