Setup checklist#
- ☐ Confirm SPF and DKIM are deployed and aligned for every legitimate sender.
- ☐ Publish _dmarc.yourdomain.com with v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com to begin collecting reports.
- ☐ Analyze aggregate (RUA) reports for 2 to 4 weeks to identify unauthenticated legitimate sources.
- ☐ Fix each source, then move to p=quarantine with pct=25, ramping to 100.
- ☐ Move to p=reject and add sp=reject to cover subdomains.
Audit checklist#
- ☐ Confirm you are not: jumping straight to p=reject and blocking your own invoicing or HR system.
- ☐ Confirm you are not: sending RUA reports to a mailbox nobody reads; use a report processor.
- ☐ Confirm you are not: leaving subdomains uncovered because sp= was never set.
- ☐ Confirm you are not: assuming p=none provides protection; it is monitoring only.
Ongoing monitoring#
- ☐ Weekly: review provider dashboards (Postmaster Tools, SNDS) and bounce logs
- ☐ Monthly: re-run the setup verification after any vendor or DNS change
- ☐ Quarterly: full audit against this checklist
Frequently asked questions#
What is DMARC alignment?
The domain in the visible From header must match (exactly or organizationally) the domain that passed SPF or DKIM. Set adkim=s and aspf=s for strict matching.
How long until I can reach p=reject?
Typically 4 to 12 weeks depending on how many third-party senders you have to fix.
What are RUA and RUF reports?
RUA are daily aggregate XML reports of pass/fail counts per source. RUF are per-message forensic samples; many receivers no longer send them.