SPF Records That Do Not Over-Permit Senders
A wide SPF record is as bad as none. Publish only the IPs and includes you actually send from, stay under ten DNS lookups, and end with -all.
Email8 min read
NetBay journal
15 practical Email articles from Netbay Engineering — written for operators running Linux and Windows VPS in India.
15 articles in this topic
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PTR, HELO, and Matching the SMTP Hostname
Receivers reject mail when PTR, HELO, and the A record disagree. Align the hostname, reverse DNS, and Postfix myhostname before you send mail.
Email8 min read
Why Transactional Email From a VPS IP Dies
Transactional mail from a new VPS IP often never reaches the inbox. This post covers blocklists, missing PTR, port 25, and when an ESP is the only path.
Email8 min read