DNS 4 NOTIMP vs 6 YXDOMAIN
Both DNS 4 (NOTIMP) and 6 (YXDOMAIN) 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, 6 means that name Exists when it should not. Used in dynamic updates to indicate a name that should not exist already has records.
説明
Not Implemented. The name server does not support the requested query type or operation.
このコードが表示される場合
You sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
解決方法
Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration.
説明
Name Exists when it should not. Used in dynamic updates to indicate a name that should not exist already has records.
このコードが表示される場合
A DNS UPDATE prerequisite check failed because the domain name already exists when the update expected it to be absent.
解決方法
Review your dynamic update prerequisites. If you expect to create a new name, remove the existing records first or change the prerequisite to allow existing names.
主な違い
DNS 4: Not Implemented. The name server does not support the requested query type or operation.
DNS 6: Name Exists when it should not. Used in dynamic updates to indicate a name that should not exist already has records.
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 6 when a DNS UPDATE prerequisite check failed because the domain name already exists when the update expected it to be absent.
どちらをいつ使うか
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 6 (YXDOMAIN): Review your dynamic update prerequisites. If you expect to create a new name, remove the existing records first or change the prerequisite to allow existing names.