There are three policy levels which can be set for DMARC.
- None – Reports possible suspicious mail messages, but all mail is sent to inbox
- Quarantine – Fail SPF/DKIM policy, then message is sent to SPAM/Junk folder
- Reject – Fail SPF/DKIM policy, then message is dropped and not delivered at all
It is strongly recommended to start with None, as this will allow for time to monitor the reports generated and determine if legitimate mail will be blocked before switching the DMARC policy to Quarantine or Reject.