DMARC

DMARC (Domain-based Message Authentication, Reporting and Conformance) is an e-mail authentication method designed to help reduce e-mail abuse. It builds upon the SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) authentication methods to provide a more reliable way to exchange email messages.

How Does DMARC work

DMARC standardizes how email receivers perform email authentication. This means that senders will experience consistent authentication results for their messages at AOL, Gmail, Hotmail, Yahoo! and any other email receiver implementing DMARC. This should encourage senders to more broadly authenticate their outbound email which can make email a more reliable way to communicate.

Acenet recommends setting up a specific email address for the DMARC feedback reports. You can use either "postmaster@" or possibly "dmarc@" your domain as the mailto address in the DNS record below.

Configuring DMARC in DNS

To enable DMARC, add a TXT record to your domain's DNS zone file.

1) Log into cPanel

2) In the Domains section of cPanel, click Advanced DNS Zone File.

3) Under Select a Domain, select the domain you want to add a record to.

4) Under Add a record, in the Name text box, type _dmarc

5) In the TTL textbox, enter 14400

6) In the Type list box, select TXT

7) In the TXT Data box, enter the DMARC configuration DATA.

{{{1}}}

8) Click Add Record.

Testing your DMARC DNS record

After adding the DNS TXT record for DMARC, please allow a few hours for DNS Propagation.

Microsoft Windows

Type nslookup at a command prompt. At the nslookup> prompt, type the following commands, replacing example.com with the actual domain name.

<syntaxhighlight lang="bash"> set type=txt _dmarc.example.com </syntaxhighlight>

You should see output that resembles the following

<syntaxhighlight lang="bash"> _dmarc.example.com text =

    "v=DMARC1;p=none;rua=mailto:[email protected]"

</syntaxhighlight>

Linux and MAC OS X

Type the following command at the command prompt. Replace example.com with your own domain name:

<syntaxhighlight lang="bash"> dig +short txt _dmarc.example.com </syntaxhighlight>

You should see output similar to the following.

<syntaxhighlight lang="bash"> "v=DMARC1; p=none; rua=mailto:[email protected]" </syntaxhighlight>