The Ultimate Guide to DNS Email Records for Better Email Deliverability 

Other than that, DNS has advanced applications in email service management, including: 

1. Load balancing: By configuring records with different priorities, DNS can direct emails to a secondary server if the primary one is down to avoid disruptions in email delivery. 
2. Routing policies: DNS lets you set routing policies to direct emails through specific gateways for scanning or archival purposes.
3. Domain verification: When setting up services, like Google Workspace for email, you have to add a DNS setting to your domain to verify that you’re the owner. 
4. Service customization: You can use DNS to set up subdomains for different departments or specific functions.

When you send an email, it goes through these steps: 

1. MX record lookup: The outgoing mail server uses DNS to look up the MX records for the recipient’s domain (example.com).
2. Identify destination email server: The MX records list the IP addresses of the mail servers designated to receive emails for the recipient’s domain, often with priority levels.
3. Route email to the primary mail server: The email is sent to the mail server with the highest priority in the MX records.
4. Fallback to secondary servers if needed: If the primary mail server is down or unreachable, the email is sent to the next available server based on the priority specified in the MX records.

Here’s a list of the main DNS records for email security. 

• Sender Policy Framework (SPF). 
• DomainKeys Identified Mail (DKIM).
• Domain-based Message Authentication, Reporting & Conformance (DMARC).

Here’s a step-by-step process to set up or modify your MX records. 

1. Log on to the DNS management dashboard provided by your domain registrar.
2. Locate the DNS settings section or the option to manage DNS records.
3. Look for the MX records configuration section.
4. Add a new MX record by specifying the priority value and the destination email server’s domain name.
5. Save the changes and wait for the DNS changes to propagate, which may take some time (usually a few hours to a day).

The string consists of the following fields: 

• Record format: A TXT record type made up of a string containing information about authorized mail servers for a domain.
• Mechanisms: SPF records use mechanisms to specify which servers can send emails on behalf of a domain. Common mechanisms include “a” for the domain’s A record, “mx” for the domain’s MX records, and “include” to include SPF records from other domains.
• Qualifiers: Qualifiers define the action to be taken when a server fails SPF authentication. Common qualifiers are “+” (Pass), “-” (Fail), “~” (SoftFail), and “?” (Neutral).

Now, you can set up SPF records by following these steps: 

1. Identify the authorized email servers.
2. Access your DNS management interface.
3. Find the DNS settings or manage DNS records.
4. Add a new TXT record.
5. Save the changes.
6. Verify the SPF record.
7. Monitor and update.

Here are a few tips to consider: 

• Use a strong qualifier, such as “~all” or “-all:” The modifier tells receiving email servers that only the servers listed in your SPF record are authorized to send emails on behalf of your domain. The first one allows the server to accept the incoming email but marks it as suspicious, while the second one outright rejects the incoming message. 
• Regularly review and update your SPF record: Email infrastructure can change over time, with new servers being added or old ones being retired. Regularly review and update your SPF record to make sure it accurately reflects your current email setup. 
• Test your SPF record. After setting up or updating an SPF record, test it to make sure it works correctly. We recommend MX Toolbox SPF Record Lookup and Mail Tester. 
• Avoid overcrowding and unnecessary mechanisms. Using too many mechanisms or IP addresses can make your SPF record unnecessarily complex and lead to errors.

Here’s a general guide:

1. Generate DKIM key pair: Use a DKIM key generator tool to create a public and private key pair. Most email services offer a dedicated tool, but you can use DMARCLY or Easy DMARC, too. You’ll save the private key on your email server and publish the public key in your DNS records.
2. Configure your email server: Set up the server to sign outgoing emails with your private DKIM key. The specifics of this process depend on your email server software, so you’ll need to consult its documentation.
3. Add the public key to Your DNS Records: Add your public key to your DNS records as a TXT record. The DNS entry should include your DKIM selector (a unique identifier for the key), the domain name, and the public key itself.
4. Test your DKIM setup: Use a DKIM validation tool to verify that your emails are being signed properly and that your DNS records are correctly configured.

Here’s how you can set up DMARC for your domain:

1. Create your DMARC policy: Decide on the DMARC policy you want to enforce. This can range from none (monitoring only) to quarantine (treat as suspicious) and reject (block outright).
2. Generate the DMARC Record: Use a DMARC record generation tool to create your DMARC record. You’ll need to input your policy preference and a couple of other options, like email addresses, for receiving reports.
3. Add the DMARC Record to DNS: Once you have your DMARC record, add it to your domain’s DNS records as a TXT record. The record should start with “v=DMARC1;” followed by your specific policy and reporting preferences.
4. Test Your DMARC Setup: Use a DMARC testing tool to validate your setup.
5. Monitor DMARC reports: DMARC reports provide insights into your email traffic and how receiving servers are handling your emails based on your DMARC policy.
6. Adjust as Needed: Based on the feedback from the DMARC reports, you might need to fine-tune your DMARC policy or your underlying SPF and DKIM settings for optimal performance.

When auditing your DNS email records, follow these best practices to ensure comprehensive and effective results:

1. Review TTL values: A lower TTL means changes to DNS records propagate faster across the internet because DNS resolvers are checking in more frequently for updates. On the other hand, A higher TTL reduces the frequency of DNS lookups, which can decrease the load on your authoritative DNS servers and increase system stability. So, you need to find a balance between flexibility and performance. 
2. Test for email deliverability: Use online tools to test if your email setup, especially SPF, DKIM, and DMARC records, is functioning properly and ensuring smooth email delivery.
3. Look for security vulnerabilities: Make sure your domain authentication protocols are properly configured, and you’re using an appropriate DMARC policy. Also, check if your domain’s TLS/SSL certificates are up-to-date. Expired certificates can lead to man-in-the-middle attacks.
4. Delete unnecessary DNS records: Look for any old or unnecessary DNS records that might be exploited or create configuration conflicts. Keeping your DNS clean reduces the attack surface.
5. Document changes: Maintain a log of changes made to your DNS settings for future reference and troubleshooting.