Use the Authentication interface to secure your mail server more secure and view information about outgoing messages. You can use this feature to verify whether an email was sent from a trusted sender.
(Home >> Email >> Authentication)
Overview
cPanel’s Authentication interface allows you to enable or disable Domain Keys Identified Mail (DKIM) and Sender Policy Framework (SPF). These features provide information about incoming mail. The system uses this information to verify that a trusted sender sent the messages.
Notes:
- Both the Domain Keys Identified Mail (DKIM) and Sender Policy Framework (SPF) authentication functions require that you use a DNS server for the domain name. For more information about DNS servers, contact your hosting provider.
You may see a warning that the system cannot verify the server as an authoritative nameserver for the specified domain name. If either of the following scenarios is true, ignore the warning:
- You designated the server as the authoritative DNS server for the domain name, but the change did not yet propagate.
- The server does not view itself as the authoritative DNS server, but outside servers view it as the authoritative DNS server.
DKIM
DKIM verifies the sender and integrity of a message. It allows an email system to prove that spammers did not alter an incoming message while in transit (forgery), and that the messages that your domains receive come from the specified domain.
- To enable DKIM, click Enable.
- To disable DKIM, click Disable.
If you already use the DSO PHP handler and you enable DKIM, emails that you send will not display any information in the Return-Path, Reply-To, or From fields in the email header. As a result, DKIM will show nobody as the sender. If you use a PHP script, manually add the headers.
The following PHP script adds the missing fields to an email header:
<?php
$to = 'nobody@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = 'From: webmaster@example.com' . "\r\n" .
'Return-Path: webmaster@example.com' . "\r\n" .
'Reply-To: webmaster@example.com' . "\r\n" .
mail($to, $subject, $message, $headers);
?>
SPF
SPF attempts to deny spammers the ability to send email while they forge your domain’s name as the sender (spoofing). SPF adds IP addresses to a list of servers that can send mail from your domains. It verifies that messages that your domains send originated from the listed server, which reduces the amount of backscatter that you receive.
- To enable SPF, click Enable.
- To disable SPF, click Disable.
Note: Run the /usr/local/cpanel/bin/spf_installer script to add an SPF record to all of a user's domains' zone files.
You can use the following Advanced Settings options to further configure SPF:
Notes:
- Click Add to add domains.
- Click Remove to remove domains.
- Click Update to save your changes.
