Build a DMARC DNS TXT record with policy, reporting addresses, and alignment modes. Roll out safely with pct slider and policy progression.
Start with none, watch reports for 2–4 weeks, then graduate.
Lower (10–50%) when rolling out new policy.
Daily XML reports from receiving mail servers.
v=DMARC1; p=quarantine; pct=100; adkim=r; aspf=r; fo=1DNS publication
Publish at _dmarc as a TXT record. Use a tool like dmarcian.com to parse the rua reports.