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duke.edu DMARC Checker

Use this DMARC checker to analyze the email authentication policy for duke.edu. DMARC builds on SPF and DKIM to control how receiving servers handle unauthenticated email claiming to come from duke.edu.

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DMARC Check for duke.edu

The DMARC record for duke.edu is published as a DNS TXT record at _dmarc.duke.edu. It tells receiving mail servers what to do when an email claiming to be from duke.edu fails SPF and DKIM authentication checks — whether to deliver it normally, send it to spam, or reject it entirely.

DMARC also provides duke.edu's administrators with visibility into who is sending email using their domain. Through aggregate reports (rua) and forensic reports (ruf), domain owners can monitor authorized and unauthorized email activity.

This DMARC checker shows duke.edu's current DMARC policy, alignment settings, and reporting configuration. A well-configured DMARC policy is essential for protecting duke.edu from email spoofing and phishing attacks.

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What Is DMARC?

DMARC is an email authentication policy layer that sits on top of SPF and DKIM. While SPF verifies the sending server and DKIM verifies the message hasn't been altered, DMARC ties them together by requiring that at least one of these checks "aligns" with the From header domain.

Without DMARC, even if duke.edu has SPF and DKIM configured, receiving servers have no instruction on what to do when authentication fails. DMARC fills this gap by providing an explicit policy (none, quarantine, or reject) and a feedback mechanism through reporting.

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DMARC Policies Explained

DMARC has three policy levels. "p=none" is monitor-only mode — authentication failures are reported but email is delivered normally. This is the recommended starting point for duke.edu when first implementing DMARC. "p=quarantine" sends failing emails to the spam/junk folder. "p=reject" blocks them entirely, providing the strongest protection.

The "pct" tag controls what percentage of failing messages the policy applies to, allowing a gradual rollout. For example, duke.edu could start with "p=reject; pct=10" to reject only 10% of failing messages while monitoring the impact, then gradually increase to 100%.

Most organizations roll out DMARC in phases: start with "p=none" to gather data, analyze reports to identify all legitimate email sources, add them to SPF/DKIM, then move to "p=quarantine" and finally "p=reject". duke.edu's current policy level reveals where it sits in this rollout.

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DMARC Alignment

DMARC requires that either SPF or DKIM "aligns" with the From header domain. For duke.edu, this means the SPF-authenticated domain or the DKIM signing domain must match duke.edu (or a subdomain of duke.edu in relaxed mode).

Alignment can be "strict" (exact domain match only) or "relaxed" (organizational domain match, allowing subdomains). The "aspf" tag controls SPF alignment and "adkim" controls DKIM alignment. Most domains use relaxed alignment (the default) because it's more flexible while still providing good protection.

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Frequently Asked Questions

Does duke.edu have DMARC? — The DMARC analysis for duke.edu shows whether the domain has a published DMARC record at _dmarc.duke.edu. If no record is found, duke.edu has not configured a DMARC policy.

What is duke.edu's DMARC policy? — The policy level (none, quarantine, or reject) is reported in the DMARC analysis. "reject" provides the strongest protection, while "none" is monitoring-only.

Does duke.edu enforce email authentication? — A DMARC policy of "quarantine" or "reject" indicates that duke.edu actively enforces email authentication. A policy of "none" means duke.edu monitors but doesn't enforce.

How do I set up DMARC for my domain? — Start by creating a TXT record at _dmarc.yourdomain.com with the value "v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com". Monitor the reports, then gradually increase enforcement to quarantine and reject.