How To Setup DMARC

Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a validation system for email that detects and prevents email spoofing.

What Is DMARC?

DMARC ensures that legitimate email is properly authenticated with previously established DKIM and SPF standards. Doing this will block fraudulent activity appearing to come from domains under the organization's control, whether they are active sending domains or not.

How To Set DMARC?

To set a DMARC record, you'll need to add a TXT record to your DNS zone. Depending on the setup of your server, how you do this can vary. If you're using a control panel, such as cPanel, you can create/edit DNS records using the Advanced Zone Editor in cPanel. Alternatively, you can add DNS records through WHM by using the Edit DNS Zone interface. The following example will illustrate how a DMARC record can look and the available different fields.

DMARC Example

v=DMARC1; p=reject; rua=mailto:mailauth-reports@exampledomain.com

Change the "mailto:" address to the email address that reports should be sent to.

The following options are available:
**None:

"v=DMARC1; p=none; sp=none; rf=afrf; pct=100; ri=86400"

Reject:

"v=DMARC1; p=reject; sp=none; rf=afrf; pct=100; ri=86400"

Quarantine:

"v=DMARC1; p=quarantine; sp=none; rf=afrf; pct=100; ri=86400"By adding an email address, you can get email reports when DMARC validations fail:None: "v=DMARC1; p=none; sp=none; ruf=mailto:mailauth-reports@exampledomain.com; rf=afrf; pct=100; ri=86400"

Reject:

"v=DMARC1; p=reject; sp=none; rf=afrf; pct=100; ruf=mailto:mailauth-reports@exampledomain.com; ri=86400"

Quarantine:

"v=DMARC1; p=quarantine; sp=none; ruf=mailto:mailauth-reports@exampledomain.com; rf=afrf; pct=100; ri=86400"