“What’s my DNS?” is a great DNS tool to check if your DNS changes have finished propagating across the internet.
Have you ever made a change to your DNS and wondered if the change has really taken effect across the whole internet? What’s my DNS? is a tool we came across that allows us to check if an A record is now pointing to the new IP address or if the CNAME and MX records have updated as well across the internet.
This DNS tool has proven itself to be very useful when we came across a website that was rendering different results after a DNS change was made. Sometimes the website would show the old version of the website, the new version or worse, nothing at all. After running What’s my DNS? on the domain’s A record, we discovered that the DNS change that was propagating across the internet had failed miserably ‐ the DNS record had corrupted. Having this information saved valuable time and allowed a single phone call to be made to the DNS provider and get the problem resolved quickly.
You can follow What’s my DNS? on Twitter at @whatsmydns.