Troubleshooting Articles
Diagnose and fix common DNS problems that cause downtime and email failures.
7 min read
What Is SERVFAIL? Understanding DNS Server Failure Responses
SERVFAIL is the DNS response code that means a resolver encountered an error during lookup. The domain might exist, but the server could not determine the answer. Learn what causes SERVFAIL, how to diagnose it, and how to fix it.
8 min read
What Is NXDOMAIN? Understanding the 'Domain Does Not Exist' DNS Response
NXDOMAIN is the DNS response code that means a domain name does not exist. Learn what triggers it, how to troubleshoot it, the difference between NXDOMAIN and SERVFAIL, and when NXDOMAIN indicates a security issue.
11 min read
DNS Troubleshooting Tools: What the Pros Actually Use
A practical overview of every DNS diagnostic tool worth knowing, from dig and nslookup to packet captures and performance testing, with real examples of when and how to use each one.
13 min read
DNS Propagation Myths Debunked: It's Really About Cache Freshness
The term 'DNS propagation' is everywhere, but it describes something that doesn't actually happen. I debunk the biggest myths and explain what's really going on: cache freshness.
11 min read
Troubleshooting Common DNS Issues: A Step-by-Step Guide
Learn how to diagnose and fix the most common DNS problems, from websites not loading to NXDOMAIN errors, using practical command-line tools and DNS Checker.