NXDOMAIN
DNS response code 3: the queried name does not exist anywhere in the DNS hierarchy.
NXDOMAIN (Non-Existent Domain, RCODE 3) is the response a DNS resolver returns when the queried name simply does not exist. It is a definitive negative answer signed by the authoritative nameserver, not a timeout or error. NXDOMAIN is cached by resolvers (governed by the SOA minimum TTL) so an unregistered or recently deleted domain may appear unreachable for hours even after it becomes valid. The opposite confusion is NOERROR with no data, which means the name exists but the requested record type does not.
Reference
Related terms
See also
Referenced on
- Build a DNS Resolver from Scratch in Node.js
- Build a DNS Resolver from Scratch in PHP
- Build a DNS Resolver from Scratch in Python
- Complete Guide to DNS Attacks and DNS Security (Prevention, Testing & Mitigation)
- DNS Amplification Attack Explained: How Open Resolvers Enable Massive DDoS
- DNS Lookups in PHP: dns_get_record, gethostbyname, and Beyond
- DNS Lookups in Python: Complete Guide with dnspython
- DNS Queries in Node.js: dns.lookup vs dns.resolve Explained
- DNS Troubleshooting Tools: What the Pros Actually Use
- DNS Water Torture Attack: How Random Subdomain Floods Overwhelm Nameservers
- DNS Zone Walking for Subdomain Enumeration: How NSEC Exposes Your Subdomains
- Email Blacklist Checker
- Fast Flux DNS: How Botnets Hide Behind Rapidly Rotating IP Addresses
- How DNS Queries Work: A Developer's Guide to the DNS Protocol
- How Expired Name Servers Become Domain Hijacking Vectors
- HTTP Status Codes Reference (1xx
- NXDOMAIN Attack: How Nonexistent Domain Floods Exhaust DNS Resolvers
- Phantom Domain Attack: How Unresponsive Domains Exhaust DNS Resolvers
- Subdomain Takeover: How Dangling DNS Records Let Attackers Hijack Your Domain
- The Complete dig Command Guide: Every Flag and Option Explained
- Troubleshooting Common DNS Issues: A Step-by-Step Guide
- Understanding DNS Record Types: A, AAAA, CNAME, MX, TXT, and More
- What Happens When One DNS Provider Goes Down: The Hidden Fragility of TLD Ecosystems
- What Is DNS Propagation and Why Does It Take So Long?
- What Is DNS TTL? How Time to Live Controls Caching, Propagation, and Performance
- What Is NXDOMAIN? Understanding the 'Domain Does Not Exist' DNS Response
- What Is SERVFAIL? Understanding DNS Server Failure Responses