DNS 0 NOERROR vs 2 SERVFAIL
Both DNS 0 (NOERROR) and 2 (SERVFAIL) belong to the DNS Response Codes (RCODEs) category. 0 indicates that no error condition. The query completed successfully and the response contains the requested data. Meanwhile, 2 means that server failure. The name server encountered an internal error while processing the query.
설명
No error condition. The query completed successfully and the response contains the requested data.
이 코드를 보게 되는 경우
This is the normal, successful response to any DNS query — the name was resolved and the answer section contains the requested records.
해결 방법
No fix needed. RCODE 0 means the DNS lookup succeeded as expected.
설명
Server failure. The name server encountered an internal error while processing the query.
이 코드를 보게 되는 경우
The recursive resolver could not get an authoritative answer — commonly caused by DNSSEC validation failures, unreachable upstream nameservers, or misconfigured zones.
해결 방법
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.
주요 차이점
DNS 0: No error condition. The query completed successfully and the response contains the requested data.
DNS 2: Server failure. The name server encountered an internal error while processing the query.
You encounter 0 when this is the normal, successful response to any DNS query — the name was resolved and the answer section contains the requested records.
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.
언제 어떤 것을 사용할지
For 0 (NOERROR): No fix needed. RCODE 0 means the DNS lookup succeeded as expected. 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.