DNS problems hide behind vague symptoms. The site won't load—but is it expired registration, slow nameservers, propagation delays, or not DNS at all? A systematic approach to finding out.
NXDOMAIN means the DNS server looked for your domain and confirmed it doesn't exist. Here's why that happens and how to fix it.
DNS cache exists at multiple levels—your OS, your browser, your ISP. Flushing one doesn't flush the others. Here's how to clear all of them.
dig and nslookup cut through DNS caches to show you raw truth—what nameservers actually know about your domain, right now, from any server you choose to ask.
DNS broke. Something asked a question and didn't get an answer. Here's how to follow the query's path and find exactly where it died.
You changed one value. Why does the Internet need 48 hours to notice? Because DNS caches are deliberately ignorant—and that's exactly why the system works.
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