Listen to this Post
Even with SPF, DKIM, and DMARC configured correctly, your emails might still land in spam due to DNS record misalignment. This happens when the domains in your SPF, DKIM, and “From” address do not align properly. Google and other email providers check for this alignment to ensure the email is not spoofed. If the domains don’t match, your emails may fail silently, passing authentication but still being filtered as spam.
How to Fix It:
- Ensure Consistency: Make sure your sending domain is consistent across SPF, DKIM, and the “From” address.
- Strict Alignment: Use strict alignment in your DMARC policy (
aspf=s; adkim=s) for better protection. - Check Email Headers: In Gmail, use “Show Original” to inspect email headers for domain mismatches.
You Should Know:
Here are some commands and tools to help you verify and troubleshoot DNS alignment:
1. Check SPF Record:
dig +short txt yourdomain.com
Look for the `v=spf1` record to ensure it includes all your sending IPs and services.
2. Verify DKIM Record:
dig +short txt default._domainkey.yourdomain.com
Ensure the DKIM public key is correctly published in your DNS.
3. DMARC Record Check:
dig +short txt _dmarc.yourdomain.com
Verify that your DMARC policy is correctly set up with `p=reject` or p=quarantine.
4. Email Header Analysis:
Use tools like Mail Tester or MX Toolbox to analyze your email headers and DNS records.
5. Gmail “Show Original”:
- Open the email in Gmail.
- Click on the three dots (More) and select “Show Original”.
- Look for
spf,dkim, and `dmarc` results to ensure alignment.
6. DMARC Report Analysis:
Use tools like GlockApps or DMARC Analyzer to analyze DMARC reports and identify alignment issues.
What Undercode Say:
DNS alignment is a critical yet often overlooked aspect of email deliverability. Misalignment can cause legitimate emails to be flagged as spam, even when SPF, DKIM, and DMARC are configured. Regularly audit your DNS records and email headers to ensure alignment. Use strict DMARC policies (aspf=s; adkim=s) for maximum protection. Tools like dig, Mail Tester, and DMARC analyzers can help you troubleshoot and maintain proper alignment. Remember, email deliverability is not just about passing authentication—it’s about ensuring every component works harmoniously.
Related Commands:
- Check DNS propagation:
nslookup yourdomain.com
- Test email deliverability:
telnet mailserver.com 25
- Verify MX records:
dig +short mx yourdomain.com
By following these steps and using the provided tools, you can ensure your emails avoid the spam folder and reach their intended recipients.
References:
Reported By: Anthony Baltodano – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
