DNS 2 SERVFAIL vs 11 DSOTYPENI
Both DNS 2 (SERVFAIL) and 11 (DSOTYPENI) belong to the DNS Response Codes (RCODEs) category. 2 indicates that server failure. The name server encountered an internal error while processing the query. Meanwhile, 11 means that dSO-TYPE Not Implemented. The DNS Stateful Operations (DSO) type in the request is not supported by the server.
説明
Server failure. The name server encountered an internal error while processing the query.
このコードが表示される場合
The recursive resolver could not get an authoritative answer — commonly caused by DNSSEC validation failures, unreachable upstream nameservers, or misconfigured zones.
解決方法
Try a different resolver (e.g., 8.8.8.8 or 1.1.1.1) to isolate the issue. If you control the zone, check DNSSEC signatures, SOA serial consistency, and nameserver reachability.
説明
DSO-TYPE Not Implemented. The DNS Stateful Operations (DSO) type in the request is not supported by the server.
このコードが表示される場合
Your client attempted a DSO operation (like a keepalive or push subscription) that the server does not recognize or has not implemented.
解決方法
Verify that both client and server support the same DSO-TYPE. Upgrade the server software or fall back to traditional DNS queries.
主な違い
DNS 2: Server failure. The name server encountered an internal error while processing the query.
DNS 11: DSO-TYPE Not Implemented. The DNS Stateful Operations (DSO) type in the request is not supported by the server.
You encounter 2 when the recursive resolver could not get an authoritative answer — commonly caused by DNSSEC validation failures, unreachable upstream nameservers, or misconfigured zones.
You encounter 11 when your client attempted a DSO operation (like a keepalive or push subscription) that the server does not recognize or has not implemented.
どちらをいつ使うか
For 2 (SERVFAIL): Try a different resolver (e.g., 8.8.8.8 or 1.1.1.1) to isolate the issue. If you control the zone, check DNSSEC signatures, SOA serial consistency, and nameserver reachability. For 11 (DSOTYPENI): Verify that both client and server support the same DSO-TYPE. Upgrade the server software or fall back to traditional DNS queries.