How do i configure DMARC?
DMARC, which stands for Domain-based Message Authentication, Reporting & Conformance, is an email authentication protocol designed to give domain owners control over how their email domain is used and to protect against email spoofing and phishing attacks. It builds on two existing email authentication techniques: SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail).
Configuration:
Implementing DMARC involves several steps to ensure that your email domain is protected against email spoofing and phishing attacks. Here’s a simplified guide to help you get started:
- Understand the Protocols:
- Familiarize yourself with SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail), as DMARC builds on these protocols.
- Set Up SPF and DKIM:
- SPF: Publish an SPF record in your domain's DNS settings to specify which mail servers are allowed to send emails on behalf of your domain.
- DKIM: Configure your email server to apply a Digital Signature to outgoing emails, and publish the public key in your DNS settings.
- Create a DMARC Record:
- A DMARC record is a DNS TXT record that includes policies and instructions for handling email. You’ll need to specify:
- Policy (p): None (monitor), quarantine, or reject.
- Aggregate Reports (rua): An email address to receive regular reports about non-compliant emails.
- Forensic Reports (ruf, optional): An email address for detailed failure reports.
- A basic DMARC record looks like this:Copy1v=DMARC1; p=none; rua=mailto:reports@example.com;
- Publish the DMARC Record:
- Add the DMARC record to your DNS under the subdomain
_dmarc
. For instance,_dmarc.example.com
.
- Monitor and Analyze Reports:
- Start with a "none" policy to collect data and monitor email traffic without impacting delivery.
- Review the reports to understand which sources are sending email on behalf of your domain and assess any authentication failures.
- Adjust the Policy:
- Gradually transition from "none" to "quarantine" and eventually to "reject" as you become confident that your legitimate emails authenticate correctly and any unauthorized sources are addressed.
- Regularly Review and Update:
- Continuously monitor DMARC reports and adjust your SPF, DKIM, and DMARC settings as necessary to maintain email authentication and address any new issues.
Implementing DMARC is a crucial step in enhancing your domain’s email security, but careful monitoring and maintenance are essential to address any potential issues that arise.