18
DNS
18 BADTIME
Signature out of time window. The TSIG signature timestamp is outside the allowed clock skew, indicating a time synchronization issue.
이 코드를 보게 되는 경우
The clocks on the DNS client and server are too far apart (usually more than 5 minutes), causing TSIG signature validation to fail.
해결 방법
Synchronize clocks on both machines using NTP. Check that the TSIG fudge value (allowed skew) is reasonable — the default 300 seconds is usually sufficient.
비교 대상
가이드
HTTP Request Lifecycle: From URL to Response
HTTP Fundamentals
Step-by-Step DNS Troubleshooting with dig and nslookup
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Improving Email Deliverability: SPF, DKIM, and DMARC Setup
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DNS Response Codes (RCODEs) Explained
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DNS TTL: How to Set TTL Values and Avoid Propagation Delays
DNS & Networking
DNS Propagation: Why Changes Take Time
DNS & Networking
DNSSEC Implementation Guide
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DNS-Based Failover and High Availability
DNS & Networking
DNS Record Types Explained: A, AAAA, CNAME, MX, TXT, and Beyond
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DNS over HTTPS (DoH) and DNS over TLS (DoT): Encrypted DNS Explained
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Essential Network Debugging Tools: ping, traceroute, mtr, and tcpdump
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