DNS 4 NOTIMP vs 7 YXRRSET
Both DNS 4 (NOTIMP) and 7 (YXRRSET) 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, 7 means that rR Set Exists when it should not. A resource record set exists that the update prerequisite says should not.
Descripción
Not Implemented. The name server does not support the requested query type or operation.
Cuándo lo verás
You sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
Cómo solucionarlo
Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration.
Descripción
RR Set Exists when it should not. A resource record set exists that the update prerequisite says should not.
Cuándo lo verás
A DNS UPDATE failed because a specific RRset (e.g., an A record) already exists when the prerequisite required it to be absent.
Cómo solucionarlo
Delete the conflicting RRset before retrying the update, or adjust your prerequisite conditions to match the actual zone state.
Diferencias clave
DNS 4: Not Implemented. The name server does not support the requested query type or operation.
DNS 7: RR Set Exists when it should not. A resource record set exists that the update prerequisite says should not.
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 7 when a DNS UPDATE failed because a specific RRset (e.g., an A record) already exists when the prerequisite required it to be absent.
Cuándo usar cada uno
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 7 (YXRRSET): Delete the conflicting RRset before retrying the update, or adjust your prerequisite conditions to match the actual zone state.