DNS 5 REFUSED vs 8 NXRRSET
Both DNS 5 (REFUSED) and 8 (NXRRSET) belong to the DNS Response Codes (RCODEs) category. 5 indicates that query refused. The name server refuses to perform the requested operation for policy reasons. Meanwhile, 8 means that rR Set that should exist does not. A required resource record set is missing from the zone.
説明
Query refused. The name server refuses to perform the requested operation for policy reasons.
このコードが表示される場合
The server rejected your query due to access control — for example, a recursive resolver that only serves its own network, or a zone transfer blocked by ACL.
解決方法
Check the server's allow-query, allow-recursion, or allow-transfer ACLs. If you are not authorized to use this resolver, switch to a public DNS service.
説明
RR Set that should exist does not. A required resource record set is missing from the zone.
このコードが表示される場合
A DNS UPDATE prerequisite expected a certain RRset to exist (e.g., an MX record), but the zone does not contain it.
解決方法
Create the missing RRset in the zone before retrying the update, or change the prerequisite to not require its existence.
主な違い
DNS 5: Query refused. The name server refuses to perform the requested operation for policy reasons.
DNS 8: RR Set that should exist does not. A required resource record set is missing from the zone.
You encounter 5 when the server rejected your query due to access control — for example, a recursive resolver that only serves its own network, or a zone transfer blocked by ACL.
You encounter 8 when a DNS UPDATE prerequisite expected a certain RRset to exist (e.g., an MX record), but the zone does not contain it.
どちらをいつ使うか
For 5 (REFUSED): Check the server's allow-query, allow-recursion, or allow-transfer ACLs. If you are not authorized to use this resolver, switch to a public DNS service. For 8 (NXRRSET): Create the missing RRset in the zone before retrying the update, or change the prerequisite to not require its existence.