DNS 2 SERVFAIL vs 17 BADKEY
Both DNS 2 (SERVFAIL) and 17 (BADKEY) 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, 17 means that key not recognized. The TSIG key name in the message is not configured on the server.
คำอธิบาย
Server failure. The name server encountered an internal error while processing the query.
เมื่อคุณพบเห็น
The recursive resolver could not get an authoritative answer — commonly caused by DNSSEC validation failures, unreachable upstream nameservers, or misconfigured zones.
วิธีแก้ไข
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.
คำอธิบาย
Key not recognized. The TSIG key name in the message is not configured on the server.
เมื่อคุณพบเห็น
Your TSIG-signed query or update references a key name that the server does not have in its keyring, so it cannot verify the signature.
วิธีแก้ไข
Ensure the TSIG key name matches exactly (case-sensitive) on both client and server. Add the missing key to the server's configuration if it is a new key.
ความแตกต่างหลัก
DNS 2: Server failure. The name server encountered an internal error while processing the query.
DNS 17: Key not recognized. The TSIG key name in the message is not configured on 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 17 when your TSIG-signed query or update references a key name that the server does not have in its keyring, so it cannot verify the signature.
ควรใช้อันไหนเมื่อไร
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 17 (BADKEY): Ensure the TSIG key name matches exactly (case-sensitive) on both client and server. Add the missing key to the server's configuration if it is a new key.