How should I enforce DMARC policies for a bulk sender with p=none?

Email marketer from Agari shares that DMARC is vital for protecting your brand against email spoofing and phishing attacks. Enforcing a strict DMARC policy ensures that unauthorized emails are blocked or quarantined, preventing malicious actors from using your domain to send fraudulent emails. This helps maintain customer trust and protects your brand reputation.

Email marketer from Valimail shares that DMARC enforcement should be approached in stages. Starting with 'p=none' allows you to gather data and identify legitimate sending sources. Before moving to 'p=quarantine' or 'p=reject', ensure all authorized sending sources are properly authenticated (SPF, DKIM). Monitor DMARC reports to identify and address any authentication failures before enforcing stricter policies to avoid disrupting legitimate email flow.

Email marketer from Email Marketing Forum explains that it’s better to wait at least a month or two at p=none to get a good handle on your email streams and authentication. Then, move to p=quarantine for a similar period before finally enforcing p=reject. This gradual approach minimizes the risk of disrupting legitimate email.

Email marketer from EasyDMARC explains the importance of using subdomains to manage email streams. Transactional and marketing emails should be sent from separate subdomains to isolate reputation. This approach makes DMARC enforcement easier, as you can apply different policies to each subdomain based on its specific needs and risk profile.

Email marketer from Postmark shares the need to closely monitor DMARC aggregate reports to identify all sending sources, including third-party services. Ensure all identified services are properly authenticated using SPF and DKIM. Contact these services to get their configuration settings. Regularly review your DMARC reports to identify and address any authentication issues before enforcing stricter policies.

Email marketer from Reddit User u/DMARC_Help shares that before moving to 'p=quarantine', make absolutely sure you understand your DMARC reports. Identify all legitimate sending sources and ensure they are correctly authenticating. If you see any unexpected sources, investigate them. Only transition to 'p=quarantine' when you are confident that legitimate emails will not be affected.

Marketer from Email Geeks explains that once all legitimate sources are authenticated and aligned, you can enforce the DMARC policies.

Email marketer from Mailjet states that if you are using multiple email service providers (ESPs), each must be correctly configured with SPF and DKIM and aligned with your DMARC policy. Coordinating DMARC implementation across multiple senders is crucial for ensuring that all legitimate emails are authenticated.

Email marketer from Proofpoint shares that the best practice for DMARC implementation involves starting with a monitoring phase ('p=none'). Analyze DMARC reports to identify all legitimate sending sources, including third-party services. Ensure that SPF and DKIM are properly configured for these sources. Once you have visibility and control over your email ecosystem, you can gradually enforce stricter DMARC policies.

Expert from Email Geeks explains that p=quarantine and p=reject are basically the same, as far as most things are concerned and mail that’s not authenticated, or which has lost authentication in transit, doesn’t get delivered.

Expert from Email Geeks shares when "you thought it was illegitimate but it was actually legit use, some service or server set up by somebody in your company without telling everybody else," it's called shadow IT, like, if an HR manager outsourced resume/applicant management to a service and that service sends mails but nobody told you about it and nobody thought to set up DKIM.

Expert from Word to the Wise explains testing DMARC records is a must for any sender implementing DMARC. She advises to use tools to test records and review the results, ensuring authentication and alignment. Start with p=none, then monitor and adjust before progressing to more strict configurations.

Expert from Email Geeks shares if they’re sending all their mail from the apex domain, and they want to go p=reject, then the only thing to do is to make sure that they’re using a good reporting service, and that someone is regularly reading those reports to look for issues and to monitor at p=none looking for problems for at least a month before moving to enforcement.

Expert from Email Geeks explains that DMARC p=reject at the apex domain will break common business use of email, to varying degrees.

Expert from Spam Resource explains that it is crucial to monitor DMARC reports diligently when initially implementing DMARC. This allows you to identify all legitimate sending sources and ensure they are properly authenticated before moving to stricter policies. Addressing authentication issues early prevents disruption of legitimate email flow.

Expert from Email Geeks shares to check any illegitimate source that has a noticeable volume. It’s not unusual for senders to have sources of mail they’re sending (though some third party, usually) that the folks in charge of the authentication don’t know about, especially if it’s a domain with multiple uses, rather than a brand domain dedicated to sending bulk mail.

Expert from Email Geeks shares if marketing and transactional emails are sent from subdomains then consider treating those subdomains separately from the apex domain.

Documentation from DMARC.org explains that the 'p=none' policy allows you to collect data without impacting email delivery. Before enforcing, ensure that your email streams are properly authenticated and aligned with DMARC requirements. After the monitoring phase, transition to 'p=quarantine' to send non-compliant emails to spam folders, and eventually to 'p=reject' to block them entirely. Regularly review aggregate reports to identify and correct any authentication issues.

Documentation from AuthSMTP shares that you should use a DMARC record checker tool to validate that your record is syntactically correct and properly configured. This tool can identify any errors in your record that may cause it to be ineffective. Make sure the syntax follows the rules.

Documentation from Google Workspace Admin Help explains that implementing DMARC involves publishing a DMARC record in your domain's DNS records. This record specifies how email receivers should handle messages that fail DMARC checks. You should start with a policy of 'p=none' to monitor your email traffic and identify any legitimate sources that are failing authentication. As you gain confidence and correct any issues, you can gradually move to stricter policies like 'p=quarantine' and 'p=reject'.

Documentation from Microsoft Learn explains that when setting up DMARC, start with 'p=none' to monitor your email traffic without affecting delivery. Review the reports generated to identify any authentication issues with legitimate email sources. Gradually move to 'p=quarantine' and 'p=reject' after verifying that all authorized sending sources are properly authenticated using SPF and DKIM.

Documentation from RFC7489 defines DMARC alignment as the process of ensuring that the domain used in the 'From:' header matches the domain used in the SPF or DKIM authentication checks. Proper alignment is critical for DMARC to function correctly. Alignment failure can lead to legitimate emails being incorrectly classified as spam or rejected.