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.
描述
Not Implemented. The name server does not support the requested query type or operation.
何时出现
You sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
如何修复
Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration.
描述
RR Set Exists when it should not. A resource record set exists that the update prerequisite says should not.
何时出现
A DNS UPDATE failed because a specific RRset (e.g., an A record) already exists when the prerequisite required it to be absent.
如何修复
Delete the conflicting RRset before retrying the update, or adjust your prerequisite conditions to match the actual zone state.
主要区别
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.
何时使用哪个
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.