Summary
Common confusions in email authentication and DMARC reporting span technical implementations, policy understanding, and ongoing maintenance. Many struggle with the complexity of setting up DMARC policies and interpreting DMARC reports, particularly the aggregate and forensic types. Specific technical issues include exceeding SPF's 10 DNS lookup limit, improper DKIM key rotation, and DNS propagation delays. Misunderstandings about the 'p=none' DMARC policy, the differences between SPF and DKIM, the importance of alignment, and the need for continuous monitoring all contribute to confusion. Incorrect DMARC record syntax and overlooking SPF's limitations with email forwarding further complicate matters. Properly implementing and maintaining SPF, DKIM, and DMARC is essential but often misconfigured.
Key findings
- Setup & Policy Complexity: DMARC setup is complex with varying policies (none, quarantine, reject) and implications.
- Reporting Challenges: DMARC aggregate and forensic reports are hard to interpret due to their complex format.
- SPF Limitations: SPF breaks with email forwarding as the forwarding server isn't authorized.
- DKIM Rotation Errors: Forgetting to update DNS after DKIM key rotation is a common error.
- p=none Misinterpretation: The 'p=none' DMARC policy is often mistaken for providing protection.
- SPF vs. DKIM Confusion: SPF and DKIM functionalities are frequently confused (server vs. content authentication).
- Alignment Neglect: Importance of DMARC alignment for authentication is frequently overlooked.
- Record Syntax Errors: DMARC record syntax errors prevent the correct implementation of DMARC.
- Ongoing Maintenance is Essential: Ongoing monitoring and adjustments are needed with DMARC.
- DNS Propagation Issues: DNS propagation times for SPF, DKIM, and DMARC records cause confusion and delays.
Key considerations
- Choose appropriate DMARC Policies: Understand the implications of DMARC policies before implementation.
- Simplify Report Analysis: Utilize tools to assist in parsing and analyzing DMARC reports effectively.
- Manage SPF for Forwarding: Address SPF issues with forwarding using SRS or similar mechanisms.
- Automate DKIM Updates: Implement procedures for automatically updating DNS records when DKIM keys are rotated.
- Move beyond p=none: Implement policies beyond P=none in DMARC records.
- Establish monitoring processes: Implement processes for regularly monitoring DMARC performance and adjusting configurations as needed.
- Validate DMARC Syntax: Ensure that DMARC record syntax is correct.
- Plan for Delays: Plan for delays after setting up your SPF, DKIM and DMARC records to ensure proper DNS propogation.
- Stay Updated: Continuously monitor and adjust email authentication based on infrastructure and changing threats.
What email marketers say
11 marketer opinions
Common confusions in email authentication and DMARC reporting stem from several areas. Many users struggle with the intricacies of setting up DMARC policies and interpreting DMARC aggregate and forensic reports. Technical aspects like SPF's limitations with forwarding, DKIM key rotation, and DNS propagation times also cause confusion. Furthermore, differentiating between SPF and DKIM, understanding the importance of alignment for DMARC, and recognizing that DMARC setup is an ongoing process, not a one-time fix, are frequent points of misunderstanding. Misinterpreting DMARC failure reasons and the implications of not implementing DMARC correctly on deliverability compound these issues.
Key opinions
- DMARC Setup Complexity: Setting up DMARC policies (none, quarantine, reject) and understanding their implications is complex.
- Report Interpretation: Many users are confused by DMARC aggregate and forensic reports, making it challenging to identify authentication failures and spoofing attempts.
- SPF Limitations: SPF breaks with email forwarding because the forwarding server isn't authorized, leading to authentication failures.
- SPF/DKIM Confusion: Users often confuse SPF and DKIM, not realizing that SPF authenticates the sending server while DKIM authenticates the message content.
- Alignment Importance: Understanding the concept of alignment and its necessity for DMARC pass is often overlooked.
- Ongoing Monitoring: DMARC setup is an ongoing process requiring continuous monitoring and adjustments.
- DNS Propagation: DNS propagation times cause confusion after setting up SPF, DKIM, and DMARC records. Changes aren't instant and updates can take up to 48 hours to apply.
Key considerations
- Understand DMARC Policies: Clearly understand the implications of 'none,' 'quarantine,' and 'reject' DMARC policies before implementing them.
- Analyze DMARC Reports: Develop a strategy for parsing and analyzing DMARC aggregate and forensic reports to identify and address authentication issues.
- Address SPF Issues: Implement solutions to handle SPF failures with email forwarding, such as using SRS (Sender Rewriting Scheme).
- Implement Both SPF and DKIM: Ensure both SPF and DKIM are correctly implemented for robust email authentication.
- Monitor DMARC Compliance: Regularly monitor DMARC compliance and adjust configurations as needed to maintain optimal deliverability.
- DNS Propagation: Consider DNS propagation times of up to 48 hours after setting up SPF, DKIM and DMARC to ensure records have been properly implemented.
Marketer view
Email marketer from MXToolbox explains that interpreting the reasons for DMARC failures, such as SPF SoftFail or DKIM signature mismatch, is a common point of confusion. Determining the root cause requires careful analysis of the reports.
7 Jan 2024 - MXToolbox Blog
Marketer view
Email marketer from StackOverflow shares that users often struggle with setting up separate DMARC records for subdomains and delegating sending authority correctly.
17 Jan 2022 - StackOverflow
What the experts say
3 expert opinions
The experts highlight several points of confusion related to email authentication and DMARC reporting. DMARC aggregate reports are difficult to understand due to their complex XML format, making it challenging to extract actionable information about authentication failures. Additionally, there's a misconception that DMARC setup is a one-time task, when in reality, ongoing monitoring and adjustments are crucial as email infrastructure and sending practices change. The DMARC reporting itself is confusing and does not make much sense.
Key opinions
- Reporting Complexity: DMARC reporting itself is confusing.
- Report Interpretation Difficulty: DMARC aggregate reports, being large XML files, are hard to parse and analyze for meaningful data.
- Ongoing Maintenance Required: DMARC setup isn't a one-time task; it requires continuous monitoring and adjustments.
Key considerations
- Invest in Report Parsing Tools: Consider using tools or services that simplify the parsing and analysis of DMARC aggregate reports.
- Establish Monitoring Processes: Implement processes for regularly monitoring DMARC performance and adjusting configurations as needed.
- Stay Updated on Email Infrastructure: Keep abreast of changes in email infrastructure and sending practices to ensure DMARC remains effective.
Expert view
Expert from Email Geeks states that the reporting is confusing. Nothing in that “evaluated” section makes much sense.
17 Nov 2024 - Email Geeks
Expert view
Expert from Word to the Wise explains that a common confusion is thinking DMARC is a one-time setup. Ongoing monitoring and adjustments are needed as email infrastructure and sending practices evolve. For example: Adjusting your SPF records or DNS records.
19 May 2024 - Word to the Wise
What the documentation says
5 technical articles
Documentation highlights several technical misunderstandings related to email authentication and DMARC reporting. A frequent issue is exceeding SPF's 10 DNS lookup limit, which can cause authentication failures. Another common mistake is failing to update DNS records after rotating DKIM keys. Additionally, many misunderstand the 'p=none' DMARC policy, believing it provides protection when it only gathers data. Incorrect DMARC record syntax, such as incorrect tag values or missing semicolons, also leads to problems. Finally, the documentation states that implementing all three of SPF, DKIM and DMARC is essential but commonly incorrectly configured or managed.
Key findings
- SPF Lookup Limit: Exceeding SPF's 10 DNS lookup limit can cause authentication failures.
- DKIM Key Rotation: Forgetting to update DNS records after rotating DKIM keys is a common mistake.
- DMARC p=none Misunderstanding: Many believe the 'p=none' DMARC policy provides protection when it only gathers data.
- DMARC Syntax Errors: Incorrect syntax in DMARC records, such as incorrect tag values or missing semicolons, can cause the record to be ignored.
- Incorrect Configuration: Implementing all three of SPF, DKIM and DMARC is essential but commonly incorrectly configured or managed.
Key considerations
- Optimize SPF Records: Ensure SPF records are optimized to stay within the 10 DNS lookup limit.
- Automate DKIM Key Rotation: Implement a process for automatically updating DNS records after DKIM key rotation.
- Choose Appropriate DMARC Policy: Select an appropriate DMARC policy ('quarantine' or 'reject') once ready to actively protect against spoofing.
- Validate DMARC Syntax: Carefully validate the syntax of DMARC records to avoid errors.
- Double check all implementations: Ensure that you have thoroughly checked the implementation of your SPF, DKIM and DMARC records to ensure they have been properly configured.
Technical article
Documentation from Google explains that a frequent misunderstanding involves SPF's 10 DNS lookup limit. Exceeding this limit can cause SPF checks to fail, impacting deliverability.
26 Feb 2024 - Google
Technical article
Documentation from RFC Editor explains that a frequent source of confusion is the correct syntax for DMARC records. Incorrect tag values or missing semicolons can cause the record to be ignored.
18 May 2023 - RFC Editor
Are DMARC RUA and RUF tags mandatory for compliance and what are their benefits?
Can DMARC reports be sent without RUA or RUF addresses?
Do all email service providers support DMARC, and what does 'support' mean in this context?
Do DMARC and BIMI require p=reject to be present on the organizational domain?
How can DMARC reports be enriched with user-level data for better domain enforcement?
How can I use DMARC to prevent spammers from using my domain?
