DNS 0 NOERROR vs 18 BADTIME
Both DNS 0 (NOERROR) and 18 (BADTIME) 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, 18 means that signature out of time window. The TSIG signature timestamp is outside the allowed clock skew, indicating a time synchronization issue.
説明
No error condition. The query completed successfully and the response contains the requested data.
このコードが表示される場合
This is the normal, successful response to any DNS query — the name was resolved and the answer section contains the requested records.
解決方法
No fix needed. RCODE 0 means the DNS lookup succeeded as expected.
説明
Signature out of time window. The TSIG signature timestamp is outside the allowed clock skew, indicating a time synchronization issue.
このコードが表示される場合
The clocks on the DNS client and server are too far apart (usually more than 5 minutes), causing TSIG signature validation to fail.
解決方法
Synchronize clocks on both machines using NTP. Check that the TSIG fudge value (allowed skew) is reasonable — the default 300 seconds is usually sufficient.
主な違い
DNS 0: No error condition. The query completed successfully and the response contains the requested data.
DNS 18: Signature out of time window. The TSIG signature timestamp is outside the allowed clock skew, indicating a time synchronization issue.
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 18 when the clocks on the DNS client and server are too far apart (usually more than 5 minutes), causing TSIG signature validation to fail.
どちらをいつ使うか
For 0 (NOERROR): No fix needed. RCODE 0 means the DNS lookup succeeded as expected. For 18 (BADTIME): Synchronize clocks on both machines using NTP. Check that the TSIG fudge value (allowed skew) is reasonable — the default 300 seconds is usually sufficient.