Start with p=none to collect reports, then tighten to quarantine or reject once all your legitimate mail passes.
DMARC
A DNS policy that tells receiving mail servers what to do when SPF and DKIM checks fail, and where to send reports.
A DNS policy that tells receiving mail servers what to do when SPF and DKIM checks fail, and where to send reports.
Start with p=none to collect reports, then tighten to quarantine or reject once all your legitimate mail passes.