DNS 2 SERVFAIL vs 3 NXDOMAIN
Both DNS 2 (SERVFAIL) and 3 (NXDOMAIN) belong to the DNS Response Codes (RCODEs) category. 2 indicates that server failure. The name server encountered an internal error while processing the query. Meanwhile, 3 means that non-Existent Domain. The queried domain name does not exist in the DNS namespace.
Descrição
Server failure. The name server encountered an internal error while processing the query.
Quando você o vê
The recursive resolver could not get an authoritative answer — commonly caused by DNSSEC validation failures, unreachable upstream nameservers, or misconfigured zones.
Como corrigir
Try a different resolver (e.g., 8.8.8.8 or 1.1.1.1) to isolate the issue. If you control the zone, check DNSSEC signatures, SOA serial consistency, and nameserver reachability.
Descrição
Non-Existent Domain. The queried domain name does not exist in the DNS namespace.
Quando você o vê
The domain has no DNS records at all — either it was never registered, has expired, or you have a typo in the hostname.
Como corrigir
Double-check the domain spelling. If you own the domain, verify your registrar settings and ensure the nameservers are correctly delegated.
Diferenças principais
DNS 2: Server failure. The name server encountered an internal error while processing the query.
DNS 3: Non-Existent Domain. The queried domain name does not exist in the DNS namespace.
You encounter 2 when the recursive resolver could not get an authoritative answer — commonly caused by DNSSEC validation failures, unreachable upstream nameservers, or misconfigured zones.
You encounter 3 when the domain has no DNS records at all — either it was never registered, has expired, or you have a typo in the hostname.
Quando usar qual
For 2 (SERVFAIL): Try a different resolver (e.g., 8.8.8.8 or 1.1.1.1) to isolate the issue. If you control the zone, check DNSSEC signatures, SOA serial consistency, and nameserver reachability. For 3 (NXDOMAIN): Double-check the domain spelling. If you own the domain, verify your registrar settings and ensure the nameservers are correctly delegated.