What is DMARC?
DMARC stands for “Domain-based Message Authentication, Reporting & Conformance”. It tells an email server what to do, after checking the validity of a domain name’s SPF and DKIM records.
How do I set up a DMARC Record in cPanel?
DMARC records are set up as TXT records inside cPanel. The steps are:
- Log in to cPanel.
- Click on the Zone Editor option.
- Click Manage next to the domain name you want to add the record for.
- Click the drop-down arrow next to the blue Add Record button, and select Add “DMARC” Record.
- Select a policy type to generate a record for.
- If you already have chosen a DMARC record, click the Raw tab to enter your custom record.
- You may click Optional Parameters to further specify how your policy works. If you’re unsure how to use these, you can simply leave them at their default values.
- Input the DMARC record into the Record/Text field.
- Click Add Record.
- Allow for 2-8 hours to pass, while the change propagates.
How do I craft a specific DMARC Record?
Firstly, here is an example of what a DMARC record might look like.
"v=DMARC1;p=reject;pct=100;rua=mailto:user@yourdomainname.com"
What does this all mean?
- v is equal to the protocol version
- p is equal to the policy for the domain name
- pct is equal to the percentage of messages that should be subject to filtering
- rua determines where any reports should be sent to (aggregated reports).
There are a couple of more advanced options, that are not included in this simplified example.
- ruf determines where “forensic reports” should be sent to.
- sp is the policy for sub-domains
- adkim sets the alignment mode for DKIM
- aspf sets the alignment mode for SPF
The easiest way to create your own DMARC record is to use the generator in cPanel, to copy the above example and simply change the email address that reports will be sent to.
