How do I configure my DMARC policy? Examples with OVH and Gandi

DMARC (or Domain-based Message Authentication, Reporting and Conformance) is a strong authentication method designed to block attempts at identity theft and fraudulent use of domain names.

Developed in 2012, the DMARC protocol has become a standard in the email world, providing a new line of defense against malicious emails. If you're not sure whether you've already configured it, you can quickly check with this DMARC verification tool.

From February 2024, the importance of DMARC

As announced by Google and Yahoo at the end of 2023, new anti-spam security criteria implemented by these platforms will block emails sent by domain names (NDD) that are not SPF, DKIM and DMARC authenticated.

Webmecanik explains these configurations in this comprehensive article.

Today, it is essential for marketers (and companies involved in email marketing) to configure DMARC on NDDs used to send marketing emails.

Setting up a DMARC policy

This is a rich and complex subject, so we suggest you contact your IT department or read this well-written documentation on DMARC from Mailjet.

To make things quick and easy, there's a "minimal" or "neutral" configuration, which will have no impact on the NDD settings and allow you to bypass the limitations of Google and Yahoo.

It consists in configuring a DNS declaring your DMARC policy as null.
None: the entry is registered, but does not lead to any action.

For example, you can configure a DMARC entry (or TXT if your host doesn't offer DMARC) with the key _dmarc and the value v=DMARC1; p=none.

For example, if your domain name is my-company-fancy.com, you'll have a DMARC or TXT entry as follows:

_dmarc 10800 IN TXT "v=DMARC1; p=none"

As mentioned in this Webmecanik DNS configuration article, you can also check that the configuration is correct using our validator.

DMARC configuration illustration with OVH and Gandi

Here's an illustration of the same neutral configuration with Gandi and OVH, two of France's leading domain name providers.

How do I set up DMARC with Gandi?

To use DMARC you need to add the following record to your domain.

_dmarc 10800 IN TXT "v=DMARC1; p=none"

The value "p" in this example means "none" (no special action taken).

Check Gandi's full documentation here, or contact their support team if you need more help.

How do I set up DMARC with OVHCloud?

There are two ways to configure DMARC in your OVHcloud DNS zone:

• Using the DMARC configuration tool. This record provides a simplified DMARC configuration. All you have to do is fill in the fields with the DMARC parameters required for your configuration. This record is read as a TXT record by DNS servers.
• Via a TXT record. This standard record can be used to configure DMARC from the OVHcloud customer area. It allows you to integrate all DMARC configuration tags, including those not present in the OVHcloud DMARC record. However, you must respect the syntax rules of the DMARC protocol.

Here's an illustration of the configuration using a TXT entry:

More information about OVHCloud DMARC can be found at this link. Don't hesitate to contact OVH support if you need further information or assistance.