Blog
DNS & email guides.
Practical guides on email authentication, domain security, and DNS monitoring. Written for ops teams and founders who want to understand what matters and skip the noise.
Deliverability
SPF, DKIM, and DMARC Explained
What each email authentication protocol does, how SPF/DKIM/DMARC alignment works, and a quick setup checklist for your domain.
January 27, 2026
DMARC Rollout Playbook
A safe, step-by-step guide to rolling out DMARC from p=none to p=reject. Includes pct ramp-up schedule and monitoring at every stage.
January 27, 2026
Why Your DMARC Reports Look Scary
Common benign senders that show up in aggregate reports, alignment issues explained, and when to worry (vs. when not to).
January 27, 2026
How to Fix SPF PermError
The 10-lookup limit explained, safe flattening strategies, provider consolidation tips, and how to keep your SPF record healthy long-term.
January 27, 2026
What Is MTA-STS and Why It Matters
How MTA-STS protects your inbound email from SMTP downgrade attacks. Includes deployment steps, testing mode, and common errors to avoid.
January 27, 2026
What Is TLS-RPT and How to Use Reports
Interpreting SMTP TLS failure reports, understanding what failure types to watch for, and setting up TLS-RPT reporting for your domain step by step.
January 27, 2026
Security & attack surface
Dangling CNAME Subdomain Takeover
How subdomain takeovers happen through dangling CNAME records, which SaaS platforms are most vulnerable, and detection and prevention strategies.
January 27, 2026
DNS Drift: What to Monitor
The DNS change feed concept — what DNS changes matter, why they happen silently, and how to catch drift before it causes incidents.
January 27, 2026
DNSSEC in Plain English
What DNSSEC protects against, how the chain of trust works from root to your zone, real-world tradeoffs, and when to deploy it.
January 27, 2026
CAA Records Explained
What CAA records do, how they prevent unauthorized SSL/TLS certificate issuance, and a step-by-step setup guide for your domain.
January 27, 2026
SMTP Downgrade Attacks and MTA-STS
How SMTP encryption downgrades work in practice, why opportunistic TLS isn't enough to stop interception, and how MTA-STS prevents downgrade attacks.
January 27, 2026
Why TLS Isn't Enough Without Policy
Why having TLS on your mail server doesn't guarantee email is encrypted in transit, and what policy mechanisms like MTA-STS and TLS-RPT close the gap.
January 27, 2026
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