Posts tagged: smtp
TLSA Record Setup: Generate & Fix the 3 1 1 Hash
Generate a TLSA record with OpenSSL, publish it, then fix the common DANE 3 1 1 mismatch. Copy-paste commands plus a free TLSA record checker. Step by step.
MTA-STS vs DANE: Verdict by Scenario (2026 Data)
Only 0.3% of 5.5M domains publish MTA-STS; 0.0% publish DANE. Get the per-scenario verdict, RFC 8461 vs 7672, Microsoft's connector modes, and NIS2 fit.
MTA-STS Example: Working Policy File & DNS Record [2026]
Copy-paste a working MTA-STS DNS record and .well-known policy file. RFC 8461 examples for Google Workspace, Microsoft 365, Postfix, plus mode progression and validators.