In today's digital landscape, email security is of utmost importance. Cyber threats, such as email spoofing and phishing, continue to pose significant risks to individuals and organizations. To combat these threats, various security measures have been developed, and one such measure is the implementation of DMARC (Domain-based Message Authentication, Reporting, and Conformance). In this article, we will guide you through the process of creating a DMARC record to enhance your email security and protect your brand.

Before diving into the technical aspects of creating a DMARC record, let's briefly discuss what DMARC is and why it matters. DMARC is an email authentication protocol that works alongside existing email authentication methods, such as SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail). It allows domain owners to specify how email receivers should handle emails that claim to be sent from their domain.

By implementing DMARC, you can:

   
• Prevent email spoofing: DMARC helps verify the authenticity of the sender's domain, making it difficult for malicious actors to forge your brand's identity.
   
• Improve email deliverability: With DMARC, you can ensure that legitimate emails sent from your domain are delivered to recipients' inboxes without being marked as spam.
   
• Gain visibility and control: DMARC provides detailed reports on email authentication results, giving you insights into unauthorized email activity and potential security threats.
 

Now that we understand the significance of DMARC, let's explore the steps involved in creating a DMARC record.

What is a DMARC Record?

Definition and Purpose

A DMARC record is a DNS (Domain Name System) record that specifies the DMARC policy for a domain. It informs email receivers how to handle emails that claim to be sent from the domain in question. The DMARC policy can be set to one of the following values: "none," "quarantine," or "reject."

Placement in DNS

To create a DMARC record, you need to add a TXT record to your domain's DNS settings. This TXT record contains the DMARC policy and other configuration parameters, allowing email receivers to authenticate and handle emails from your domain correctly.

Format and Naming Convention

A DMARC record follows a specific format and naming convention. It begins with "v=DMARC1," indicating that it is a DMARC record. This is followed by various tags and their corresponding values, separated by semicolons. These tags provide instructions and configuration details for the DMARC policy.

Generating a DMARC Record

Creating a DMARC record manually can be complex, especially if you are not familiar with the syntax and tags involved. However, there are user-friendly tools available that can simplify the process and generate DMARC records for you.

Using DMARC Analyzer and Record Generator

DMARC Analyzer is a widely used tool that simplifies the creation and management of DMARC records. It offers a user-friendly interface where you can configure your DMARC policy settings and generate the corresponding DMARC record. The tool also provides valuable insights and reports to help you monitor and improve your email authentication.

To generate a DMARC record using DMARC Analyzer, follow these steps:

   
1. Visit the DMARC Analyzer website and sign up for an account if you haven't already.
   
2. Access the DMARC record generator within the platform.
   
3. Configure your desired DMARC policy settings, such as the policy type ("none," "quarantine," or "reject"), alignment mode, and reporting options.
   
4. Once you have specified your preferences, the tool will generate the DMARC record for your domain.
   
5. Copy the generated DMARC record and proceed to the next step of configuring it in your DNS settings.
 

Required and Optional Tags in DMARC TXT Records

When generating a DMARC record, it's essential to understand the required and optional tags that can be included. The required tags are:

   
• "v" tag: This tag specifies the DMARC protocol version and should always be set to "DMARC1."
   
• "p" tag: This tag defines the DMARC policy and can be set to "none," "quarantine," or "reject."
 

In addition to the required tags, there are optional tags that allow you to fine-tune your DMARC policy. Some commonly used optional tags include:

   
• "sp" tag: This tag defines the DMARC policy for subdomains of your domain.
   
• "pct" tag: This tag specifies the percentage of emails that should be subjected to the DMARC policy. It is useful for gradually deploying DMARC policies.
   
• "rua" tag: This tag specifies the email address where aggregate DMARC reports should be sent.
   
• "ruf" tag: This tag defines the email address where forensic DMARC reports should be sent.
 

Understanding DMARC Policies

Before finalizing your DMARC policy settings, it's crucial to understand the implications of each policy type. You may want to refer to this comprehensive guide on DMARC policies by Postmark.

   
• "none" policy: This policy is used for monitoring purposes, allowing you to collect DMARC reports without taking any immediate action on failed emails. It is recommended to start with this policy during the initial implementation phase.
   
• "quarantine" policy: With this policy, emails that fail DMARC authentication are treated with caution and may be placed in the recipient's spam or quarantine folder. This policy provides a balance between email deliverability and security.
   
• "reject" policy: This policy instructs email receivers to reject emails that fail DMARC authentication. The rejected emails will not reach the recipient's inbox, providing the highest level of security but potentially affecting legitimate email deliverability.
 

Carefully consider your organization's email infrastructure and security requirements when selecting the appropriate DMARC policy.

Configuring DMARC Policies

Once you have generated the DMARC record, it's time to configure the DMARC policy settings according to your requirements. The DMARC policy is defined by the "p" tag in the DMARC record and can be set to "none," "quarantine," or "reject." Let's explore each policy in detail.

None Policy

The "none" policy is the recommended starting point for implementing DMARC. When using the "none" policy, email receivers will not take any action on emails that fail DMARC authentication. Instead, they will send aggregate DMARC reports to the specified email address, allowing you to monitor email authentication results.

Quarantine Policy

The "quarantine" policy provides a middle ground between the "none" and "reject" policies. When using the "quarantine" policy, email receivers may place emails that fail DMARC authentication in the recipient's spam or quarantine folder.

Implementing the "quarantine" policy requires careful consideration, as it can impact legitimate email delivery. It is recommended to analyze DMARC reports thoroughly and fine-tune your email sources before transitioning to the "quarantine" policy.

Reject Policy

The "reject" policy offers the highest level of security but can also impact legitimate email delivery. With the "reject" policy, email receivers reject emails that fail DMARC authentication, preventing them from reaching the recipient's inbox.

Before transitioning to the "reject" policy, it is essential to have a deep understanding of your email infrastructure, legitimate email sources, and potential authentication issues. Thoroughly analyze DMARC reports and ensure that your legitimate email sources are aligned with DMARC requirements.

Choosing the Appropriate DMARC Policy

Choosing the appropriate DMARC policy depends on various factors, including your organization's email infrastructure, level of control, and desired balance between security and email deliverability. It is recommended to start with the "none" policy during the initial implementation phase, gradually monitor and analyze DMARC reports, and then make informed decisions regarding the policy type.

Remember that implementing DMARC is an iterative process. It requires ongoing monitoring, analysis, and adjustments to ensure a successful implementation while maintaining legitimate email delivery.

Creating a DMARC Record

Now that you have a better understanding of DMARC policies, alignment modes, and other configuration options, let's dive into the process of creating a DMARC record.

Alignment Mode (aspf / adkim)

DMARC alignment modes play a crucial role in verifying the authenticity of the email's domain. There are two alignment modes:

   
• aspf (Authenticated Sender Policy Framework): This mode verifies if the domain in the "From" header matches the domain used in the SPF authentication.
   
• adkim (Author Domain Key Identified Mail): This mode checks if the domain in the "From" header aligns with the DKIM signature.
 

You can specify the alignment modes in your DMARC record using the "aspf" and "adkim" tags. The recommended values for these tags are "r" (relaxed) or "s" (strict). The relaxed mode allows minor domain mismatches, while the strict mode requires an exact match.

Choose the alignment modes that best suit your email infrastructure and authentication practices.

Including Email Address for Reports (rua tag)

To receive DMARC reports, you need to specify the email address where aggregate reports should be sent. This is done using the "rua" tag in your DMARC record. The reports provide valuable insights into email authentication results, allowing you to identify potential security threats and unauthorized email activity.

Make sure to configure a valid email address to receive these reports and regularly analyze them to ensure the effectiveness of your DMARC implementation.

Setting up TXT Record with Domain Host

Once you have finalized your DMARC record with all the necessary tags and values, it's time to add the TXT record to your domain's DNS settings. This step may vary depending on your domain host or DNS provider.

   
1. Log in to your domain hosting account or DNS provider's website.
   
2. Navigate to the DNS management section for the domain you want to configure.
   
3. Add a new TXT record with the following details:
   

     
• Host/Name: Enter the name of the host or domain where you want to apply the DMARC policy (e.g., "@," which represents the root domain).
     
• Value/Text: Paste the generated DMARC record, including all the tags and values.
     
• TTL (Time to Live): Set an appropriate TTL value (e.g., 3600 seconds).
   

   
1. Save the changes and allow some time for the DNS changes to propagate.
 

Note that DNS propagation can take up to 24 hours, although it usually happens much faster. During this time, it's crucial to avoid making further changes to your DMARC record.

DMARC Record Setup Tools

While the process of creating and configuring a DMARC record may seem complex, there are several tools available to simplify the setup and ensure accuracy.

DMARC Record Generator

As mentioned earlier, tools like DMARC Analyzer offer a DMARC record generator. These tools guide you through the process, helping you configure your desired DMARC policy settings and generating the corresponding DMARC record. They also provide helpful explanations and recommendations to enhance your email security.

DMARC Record Checker

After creating and configuring your DMARC record, it's essential to validate its correctness. DMARC record checkers allow you to verify the syntax and structure of your DMARC record, ensuring that it adheres to the required format. These tools highlight any potential errors or issues that need to be addressed.

Record Setup Guides for Specific Webhosts

Different web hosts and DNS providers may have slightly different procedures for setting up DMARC records. Many hosting companies offer specific setup guides or tutorials to help their users create DMARC records correctly. Consult the documentation provided by your web host or DNS provider for detailed instructions on adding a DMARC record to your domain's DNS settings.

User-Friendly DMARC Analyzing Software

In addition to generating DMARC records, there are advanced DMARC analyzing software solutions available. These tools provide comprehensive insights into your email authentication results, including detailed reports, graphical representations, and actionable recommendations. They simplify the monitoring and analysis process, allowing you to proactively enhance your email security.

Example DMARC Report

Once your DMARC record is set up and your email system starts sending emails, you will begin receiving DMARC reports. These reports contain valuable information about the authentication status of the emails sent on behalf of your domain.

Understanding DMARC Reports

DMARC reports provide insights into various aspects of email authentication, including:

   
• Email volume: The number of emails sent on behalf of your domain.
   
• Authentication results: The percentage of emails that pass or fail SPF, DKIM, or DMARC alignment checks.
   
• Sources and IP addresses: The IP addresses and sources from which the emails claiming to be from your domain were sent.
   
• Authentication failures: Detailed information about the emails that failed authentication, including their headers and authentication results.
 

Analyzing these reports helps you identify potential threats, unauthorized email sources, and configuration issues that may affect your email deliverability and security.

Analyzing Outbound Mail Sources

One of the crucial aspects of DMARC reports is analyzing the sources from which emails claiming to be from your domain are sent. By reviewing the IP addresses and sources, you can verify if they align with your legitimate email infrastructure. If you notice any unfamiliar or unauthorized sources, it's crucial to investigate further and take appropriate action to mitigate any potential security risks.

Ensuring IP Authenticity and Configuration

DMARC reports also help you ensure the authenticity and proper configuration of the IP addresses used to send emails on behalf of your domain. By validating the IP addresses and checking for any configuration issues, you can prevent unauthorized senders from using your domain for malicious activities.

Deploying DMARC Policy Gradually

Deploying a DMARC policy should be a gradual process to avoid any unintended impact on your legitimate email delivery. Here are some recommended steps for a smooth deployment:

Recommended Deployment Order

   
1. Start with the "none" policy: Begin by configuring your DMARC record with the "none" policy.
   
2. Analyze DMARC reports: Regularly review the DMARC reports to gain insights into your email sources, authentication results, and potential threats.
   
3. Fine-tune email sources: Based on the analysis of DMARC reports, identify and align your legitimate email sources with DMARC requirements. This may involve adjusting SPF and DKIM configurations or addressing any authentication failures.
   
4. Transition to "quarantine" policy: Once you have verified and aligned your legitimate email sources, consider transitioning to the "quarantine" policy. This cautious approach allows you to monitor the impact on email deliverability while maintaining a higher level of security.
   
5. Monitor and analyze: Continuously monitor the DMARC reports and analyze the effects of the "quarantine" policy on your email delivery. Make necessary adjustments and improvements as needed.
   
6. Transition to "reject" policy: After carefully evaluating the impact of the "quarantine" policy and ensuring that your legitimate email sources are aligned, you can consider transitioning to the strictest "reject" policy. This policy provides maximum security by rejecting unauthorized emails at the receiving end.
 

Monitoring Traffic and Anomalies

Throughout the deployment process, it's crucial to closely monitor your email traffic and look for any anomalies or unexpected changes. Keep an eye on bounce rates, spam folder placement, and feedback from recipients to ensure that your legitimate emails continue to be delivered correctly.

Transitioning from "none" to "quarantine"

When transitioning from the "none" policy to the "quarantine" policy, it's essential to carefully monitor the impact on email deliverability. Start with a small percentage of emails subjected to the "quarantine" policy and gradually increase the percentage over time, based on the analysis of DMARC reports and the performance of your legitimate email sources.

Transitioning from "quarantine" to "reject"

Similar to transitioning from "none" to "quarantine," the transition from the "quarantine" policy to the strictest "reject" policy should be gradual. Monitor the impact on email deliverability and take necessary precautions to ensure that your legitimate emails are not affected.

Using the Optional pct Tag for Staging

The "pct" (percentage) tag in the DMARC record allows you to specify the percentage of emails that should be subjected to the DMARC policy. This tag is useful for staging the deployment of DMARC policies. Starting with a low percentage, such as 10% or 20%, enables you to assess the impact on email deliverability before gradually increasing the percentage.

Conservative Deployment Cycle

Remember that deploying DMARC policies is an iterative process that requires careful planning and monitoring. It is recommended to adopt a conservative deployment cycle, allowing sufficient time to analyze DMARC reports and fine-tune your email sources and configurations. By taking a cautious approach, you can minimize the risk of unintended consequences on your email delivery while strengthening your email security.

Creating Your Own DMARC Record

While tools like DMARC Analyzer simplify the process of generating a DMARC record, you may also choose to create it manually. However, creating a DMARC record manually requires a good understanding of the DMARC syntax and tags.

DMARC Record Generator

If you prefer creating a DMARC record manually, it's still helpful to use a DMARC record generator tool to ensure accuracy and compliance with the required format. These tools allow you to input the desired DMARC policy settings and generate the corresponding DMARC record with the correct syntax and structure.

Verifying Email Flow Configuration

When creating a DMARC record manually, it's crucial to verify your email flow configuration to ensure that all outgoing emails are aligned with DMARC requirements. This involves configuring SPF and DKIM for your email servers, properly authenticating email sources, and ensuring consistent domain alignment.

Conclusion

Implementing a DMARC record is a vital step in enhancing your email security and protecting your brand from email spoofing and phishing attacks. By creating a DMARC record and configuring the appropriate policies, you can verify the authenticity of emails sent from your domain and gain greater control over email deliverability.

However, we understand that this technical information can be complex and overwhelming for many organizations. That's where Palisade.Email can assist you. Our team of experts is well-versed in DMARC implementation and can help you assess where you are in the process and determine the next steps you need to take.

To get started, we invite you to fill out our 2-minute questionnaire, where we will gather essential information about your email infrastructure and security goals. By understanding your specific needs, we can provide tailored guidance and support to ensure a successful DMARC implementation.

Don't let email security be a barrier to your business success. Take the first step by filling out our questionnaire at and let Palisade help you strengthen your email security today.

External Links:

   
• DMARC Analyzer