18
DNS
18 BADTIME
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.
比較対象
ガイド
HTTP Request Lifecycle: From URL to Response
HTTP Fundamentals
Step-by-Step DNS Troubleshooting with dig and nslookup
Debugging & Troubleshooting
Improving Email Deliverability: SPF, DKIM, and DMARC Setup
Email Delivery
DNS Response Codes (RCODEs) Explained
DNS & Networking
DNS TTL: How to Set TTL Values and Avoid Propagation Delays
DNS & Networking
DNS Propagation: Why Changes Take Time
DNS & Networking
DNSSEC Implementation Guide
DNS & Networking
DNS-Based Failover and High Availability
DNS & Networking
DNS Record Types Explained: A, AAAA, CNAME, MX, TXT, and Beyond
DNS & Networking
DNS over HTTPS (DoH) and DNS over TLS (DoT): Encrypted DNS Explained
DNS & Networking
Essential Network Debugging Tools: ping, traceroute, mtr, and tcpdump
DNS & Networking
Resource Hints: Preload, Prefetch, Preconnect, and DNS-Prefetch
Performance & Optimization
RFC 9114: HTTP/3 Protocol Deep Dive
Protocol Deep Dives
RFC 3261: SIP Protocol Deep Dive
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QUIC Protocol: The Transport Layer Behind HTTP/3
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Migrating from TLS 1.2 to TLS 1.3: Configuration and Compatibility
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Secret Management for API Keys, Tokens, and Certificates
Production Infrastructure
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