DNS 4 NOTIMP vs 20 BADNAME
Both DNS 4 (NOTIMP) and 20 (BADNAME) belong to the DNS Response Codes (RCODEs) category. 4 indicates that not Implemented. The name server does not support the requested query type or operation. Meanwhile, 20 means that duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
설명
Not Implemented. The name server does not support the requested query type or operation.
이 코드를 보게 되는 경우
You sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
해결 방법
Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration.
설명
Duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
이 코드를 보게 되는 경우
A TKEY key establishment failed because a key with the same name already exists on the server from a previous session that was not properly cleaned up.
해결 방법
Use a unique key name for each TKEY session (e.g., append a timestamp or random suffix). Delete stale keys on the server if they are no longer needed.
주요 차이점
DNS 4: Not Implemented. The name server does not support the requested query type or operation.
DNS 20: Duplicate key name. The key name in a TKEY negotiation is already in use or conflicts with an existing key.
You encounter 4 when you sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
You encounter 20 when a TKEY key establishment failed because a key with the same name already exists on the server from a previous session that was not properly cleaned up.
언제 어떤 것을 사용할지
For 4 (NOTIMP): Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration. For 20 (BADNAME): Use a unique key name for each TKEY session (e.g., append a timestamp or random suffix). Delete stale keys on the server if they are no longer needed.