This test checks to make sure that none of your registered public name servers have private IP Addresses, that is, IP Addresses which are not publicly routable.
This issue can commonly occur if you have internal DNS name servers with Private IP Addresses that your employees use and those Private IP Addresses are accidentally published in your zone file.
Additional Information
For more information about private or reserved IP Addresses, this Wikipedia article is a great reference to multiple RFCs that cover this topic; most notably RFC 1918 and RFC 5735.
Your Email Deliverability is in Jeopardy!
Blacklisting is a sign that you are not actively managing your email deliverability. Other technologies - SPF, DKIM and DMARC are now just as important to get your email placed in the Inbox of your recipients. If you aren’t managing email deliverability, your message may never be heard.
MxToolbox Delivery Center Features:
- Insight into your SPF, DKIM and DMARC configuration to ensure your sending email properly
- DMARC Compliance checks for all of your reported email
- Adaptive Blacklist Monitoring of all your email senders
- Recommendations for improving DMARC compliance and DMARC policies
- Event-based reminders for emergent issues and on-going maintenance
DMARC is a necessity for your business!
Learn More about Email Delivery