DNS 0 NOERROR vs 16 BADVERS/BADSIG
Both DNS 0 (NOERROR) and 16 (BADVERS/BADSIG) belong to the DNS Response Codes (RCODEs) category. 0 indicates that no error condition. The query completed successfully and the response contains the requested data. Meanwhile, 16 means that bad OPT Version or TSIG Signature Failure. Either the EDNS version in the OPT record is not supported, or the TSIG signature on the message failed verification.
الوصف
No error condition. The query completed successfully and the response contains the requested data.
متى تراه
This is the normal, successful response to any DNS query — the name was resolved and the answer section contains the requested records.
كيفية الإصلاح
No fix needed. RCODE 0 means the DNS lookup succeeded as expected.
الوصف
Bad OPT Version or TSIG Signature Failure. Either the EDNS version in the OPT record is not supported, or the TSIG signature on the message failed verification.
متى تراه
As BADVERS: your client sent an EDNS version higher than the server supports. As BADSIG: the TSIG MAC on the message did not match, indicating a shared-secret mismatch or message tampering.
كيفية الإصلاح
For BADVERS, downgrade the EDNS version (most servers support version 0 only). For BADSIG, regenerate and re-synchronize the TSIG shared secret on both endpoints.
الفروق الرئيسية
DNS 0: No error condition. The query completed successfully and the response contains the requested data.
DNS 16: Bad OPT Version or TSIG Signature Failure. Either the EDNS version in the OPT record is not supported, or the TSIG signature on the message failed verification.
You encounter 0 when this is the normal, successful response to any DNS query — the name was resolved and the answer section contains the requested records.
You encounter 16 when as BADVERS: your client sent an EDNS version higher than the server supports. As BADSIG: the TSIG MAC on the message did not match, indicating a shared-secret mismatch or message tampering.
متى تستخدم أيًا منهما
For 0 (NOERROR): No fix needed. RCODE 0 means the DNS lookup succeeded as expected. For 16 (BADVERS/BADSIG): For BADVERS, downgrade the EDNS version (most servers support version 0 only). For BADSIG, regenerate and re-synchronize the TSIG shared secret on both endpoints.