SSL MOON

DMARC (Domain-based Message Authentication, Reporting and Conformance) is a DNS TXT record at _dmarc that tells receiving mail servers how to handle messages that fail SPF or DKIM, and where to send reports.

An enforcing DMARC policy is published (p=quarantine).
DMARC record v=DMARC1; p=quarantine; pct=100; rua=mailto:backup@zbor.md; ruf=mailto:backup@zbor.md; adkim=r; aspf=r;