DNS 1 FORMERR vs 19 BADMODE
Both DNS 1 (FORMERR) and 19 (BADMODE) 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, 19 means that bad TKEY Mode. The TKEY mode field contains a value not supported by the server.
설명
Format error. The name server was unable to interpret the query due to a malformed DNS message.
이 코드를 보게 되는 경우
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.
해결 방법
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.
설명
Bad TKEY Mode. The TKEY mode field contains a value not supported by the server.
이 코드를 보게 되는 경우
Your client attempted a TKEY key exchange using a mode (e.g., Diffie-Hellman, GSS-API) that the server does not support or has not been configured for.
해결 방법
Check which TKEY modes the server supports and configure your client to use a compatible mode. GSS-TSIG (mode 3) is the most widely deployed.
주요 차이점
DNS 1: Format error. The name server was unable to interpret the query due to a malformed DNS message.
DNS 19: Bad TKEY Mode. The TKEY mode field contains a value not supported by the server.
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 19 when your client attempted a TKEY key exchange using a mode (e.g., Diffie-Hellman, GSS-API) that the server does not support or has not been configured for.
언제 어떤 것을 사용할지
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 19 (BADMODE): Check which TKEY modes the server supports and configure your client to use a compatible mode. GSS-TSIG (mode 3) is the most widely deployed.