DNS 1 FORMERR vs 3 NXDOMAIN
Both DNS 1 (FORMERR) and 3 (NXDOMAIN) belong to the DNS Response Codes (RCODEs) category. 1 indicates that format error. The name server was unable to interpret the query due to a malformed DNS message. Meanwhile, 3 means that non-Existent Domain. The queried domain name does not exist in the DNS namespace.
描述
Format error. The name server was unable to interpret the query due to a malformed DNS message.
何时出现
Your DNS client or library sent a query the server could not parse, often caused by a buggy resolver, corrupted packet, or unsupported EDNS options.
如何修复
Check your DNS client or library version for known bugs. Capture the raw query with dig or Wireshark and verify it conforms to the DNS wire format.
描述
Non-Existent Domain. The queried domain name does not exist in the DNS namespace.
何时出现
The domain has no DNS records at all — either it was never registered, has expired, or you have a typo in the hostname.
如何修复
Double-check the domain spelling. If you own the domain, verify your registrar settings and ensure the nameservers are correctly delegated.
主要区别
DNS 1: Format error. The name server was unable to interpret the query due to a malformed DNS message.
DNS 3: Non-Existent Domain. The queried domain name does not exist in the DNS namespace.
You encounter 1 when your DNS client or library sent a query the server could not parse, often caused by a buggy resolver, corrupted packet, or unsupported EDNS options.
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.
何时使用哪个
For 1 (FORMERR): Check your DNS client or library version for known bugs. Capture the raw query with dig or Wireshark and verify it conforms to the DNS wire format. For 3 (NXDOMAIN): Double-check the domain spelling. If you own the domain, verify your registrar settings and ensure the nameservers are correctly delegated.