Can I use DMARC with shared IP addresses?
Summary
What email marketers say12Marketer opinions
Marketer from Email Geeks confirms that a shared IP pool can be included in an aligned SPF record.
Email marketer from Email Geeks suggests that users who implement DMARC when using an ESP with shared IP addresses should start with a reporting-only policy (p=none) to monitor DMARC reports.
Email marketer from Postmark answers that you can use DMARC with shared IPs, but it's important to understand the implications for SPF. If the shared IPs are not properly included in your SPF record, DMARC may fail. Using DKIM is a good way to improve the success of DMARC in this scenario.
Email marketer from Email Geeks explains that either SPF or DKIM needs to be in alignment for DMARC to pass, but ideally both should pass and be aligned. Recommends implementing DMARC for reporting first and then moving slowly towards an enforcing policy.
Email marketer from an Email Marketing Forum responds that the key to using DMARC with shared IPs is ensuring SPF alignment. If the shared IPs used by your ESP are included in the SPF record for your domain, DMARC will work correctly. If SPF alignment is a concern, DKIM alignment can also provide the necessary authentication.
Email marketer from Reddit shares that implementing DMARC when using an ESP with shared IPs is a good practice. Start with a 'p=none' policy to monitor reports and assess the impact before enforcing stricter policies. Ensure SPF and DKIM are correctly configured for optimal results.
Marketer from Email Geeks clarifies that to implement a DMARC record you need the IPs listed in the SPF record, and the SPF record must be aligned.
Email marketer from StackOverflow shares that DMARC is domain-centric and cares about SPF/DKIM alignment, not the type of IP address used to send the email. As long as either SPF or DKIM is aligned, DMARC will pass, irrespective of whether you're using a shared or dedicated IP.
Email marketer from EmailonAcid answers that implementing DMARC with shared IPs requires careful attention to SPF configuration. Since multiple senders use the same IPs, ensure the ESP’s IPs are included in your SPF record to avoid deliverability issues. Always start with a relaxed policy (p=none) to monitor the impact.
Email marketer from SendGrid answers that DMARC functions independently of the underlying email infrastructure, which means it's fully compatible with shared IP addresses. The focus is on the alignment between the domain in the 'From' header and the results of SPF and DKIM checks. As long as these checks align, DMARC will work as intended.
Email marketer from Mailjet answers that using DMARC with shared IPs is possible and recommended. DMARC authenticates based on the domain, so the IP configuration doesn't prevent its use. However, proper SPF and DKIM setup is crucial.
Email marketer from SparkPost answers that DMARC can be effectively used with shared IPs, especially when combined with DKIM. They suggest that DKIM provides a more robust authentication method in shared IP environments where SPF can be more challenging to configure correctly.
What the experts say6Expert opinions
Expert from Email Geeks explains that DMARC cares about DKIM and SPF, and only one needs to be aligned.
Expert from Email Geeks confirms that you can have a DMARC record for any domain, regardless of the IP configuration.
Expert from Word to the Wise, Laura Atkins, responds that implementing DMARC in a shared IP environment is possible, but requires coordination with the ESP (Email Service Provider). She emphasizes the importance of ensuring that the ESP’s sending infrastructure is properly configured with SPF and DKIM. Additionally, careful monitoring of DMARC reports is essential for identifying and addressing any authentication issues.
Expert from Email Geeks clarifies that DMARC doesn't care about shared vs dedicated IPs.
Expert from Spam Resource, John Levine, explains that using DMARC with shared IPs requires careful attention to SPF. When multiple senders share an IP, SPF records must authorize all legitimate senders. Problems arise when one sender's spam activity impacts the reputation of the shared IP, affecting DMARC results for all senders using that IP. He recommends carefully managing SPF records and monitoring sender reputation.
Expert from Email Geeks states that DMARC is not dependent on IPs, it's a domain-level tool, unlike SPF which is IP dependent.
What the documentation says4Technical articles
Documentation from Google Workspace Admin Help explains that DMARC relies on SPF and DKIM to authenticate emails. While using shared IPs is not a direct impediment to DMARC, ensuring that the shared IPs are properly included in your SPF record and that DKIM is correctly configured is essential for DMARC to function effectively.
Documentation from DMARC.org explains that DMARC is designed to work independently of the IP address infrastructure. DMARC focuses on the domain in the 'From:' header of an email, not the IP address from which the email was sent. Therefore, it is perfectly acceptable and common to use DMARC with shared IP addresses.
Documentation from Microsoft outlines the steps for setting up DMARC, emphasizing that it is compatible with shared IP environments. They recommend checking SPF and DKIM records and using monitoring tools to understand how DMARC is working for your domain. Proper configuration is key, regardless of the IP arrangement.
Documentation from RFC 7489 (the DMARC standard) answers that DMARC's evaluation scope is the domain found in the RFC5322.From header field. It is not directly concerned with the IP address used to transmit the message, making it compatible with shared IP environments provided other requirements like SPF/DKIM alignment are met.