{"id":5245,"date":"2026-02-06T23:33:10","date_gmt":"2026-02-06T23:33:10","guid":{"rendered":"https:\/\/securitybriefing.net\/?p=5245"},"modified":"2026-02-06T23:52:27","modified_gmt":"2026-02-06T23:52:27","slug":"%e9%81%85%e3%81%84dns%e3%83%ab%e3%83%83%e3%82%af%e3%82%a2%e3%83%83%e3%83%97%e3%82%92%e4%bf%ae%e6%ad%a3%e3%81%99%e3%82%8b%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/securitybriefing.net\/ja\/%e3%83%86%e3%82%af%e3%83%8e%e3%83%ad%e3%82%b8%e3%83%bc\/%e9%81%85%e3%81%84dns%e3%83%ab%e3%83%83%e3%82%af%e3%82%a2%e3%83%83%e3%83%97%e3%82%92%e4%bf%ae%e6%ad%a3%e3%81%99%e3%82%8b%e6%96%b9%e6%b3%95\/","title":{"rendered":"\u9045\u3044DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u4fee\u6b63\u3059\u308b\u65b9\u6cd5"},"content":{"rendered":"<p>\u9045\u3044DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u306f\u3001\u30d6\u30e9\u30a6\u30b6\u304c\u30a6\u30a7\u30d6\u30da\u30fc\u30b8\u306e\u8aad\u307f\u8fbc\u307f\u3092\u958b\u59cb\u3059\u308b\u524d\u306b\u4e0d\u8981\u306a\u9045\u5ef6\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u901a\u5e38\u306eDNS\u89e3\u6c7a\u306b\u306f20\u301c120\u30df\u30ea\u79d2\u304b\u304b\u308a\u307e\u3059\u304c\u3001\u8a2d\u5b9a\u30df\u30b9\u3084\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u4f4e\u3044DNS\u306f\u305d\u308c\u3092100\u30df\u30ea\u79d2\u3092\u8d85\u3048\u3066\u62bc\u3057\u4e0a\u3052\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u6642\u9593\u306f\u3001\u30b3\u30a2\u30a6\u30a7\u30d6\u30d0\u30a4\u30bf\u30eb\u6307\u6a19\u3067\u3042\u308b\u30d5\u30a1\u30fc\u30b9\u30c8\u30d0\u30a4\u30c8\u307e\u3067\u306e\u6642\u9593\uff08TTFB\uff09\u306b\u76f4\u63a5\u5f71\u97ff\u3057\u307e\u3059\u3002Google\u306e\u8abf\u67fb\u306b\u3088\u308b\u3068\u3001\u30da\u30fc\u30b8\u306e\u8aad\u307f\u8fbc\u307f\u6642\u9593\u304c3\u79d2\u304b\u30895\u79d2\u306b\u5897\u3048\u308b\u3068\u3001\u30d0\u30a6\u30f3\u30b9\u78ba\u7387\u304c32%\u304b\u308990%\u306b\u8df3\u306d\u4e0a\u304c\u308a\u307e\u3059\u3002\u826f\u3044\u30cb\u30e5\u30fc\u30b9\u306f\u3001\u307b\u3068\u3093\u3069\u306e\u539f\u56e0\u306f\u8a3a\u65ad\u3068\u4fee\u6b63\u304c\u7c21\u5358\u3067\u3042\u308b\u3053\u3068\u3067\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n<h2 class=\"wp-block-heading\" id=\"contents\">\u76ee\u6b21<\/h2>\n\n\n<ol class=\"wp-block-list\">\n<li><a href=\"#causes\">\u9045\u3044DNS\u306e\u539f\u56e0<\/a><\/li>\n\n\n\n<li><a href=\"#diagnose\">\u30b9\u30c6\u30c3\u30d71: \u554f\u984c\u306e\u8a3a\u65ad<\/a><\/li>\n\n\n\n<li><a href=\"#restart\">\u30b9\u30c6\u30c3\u30d72: \u30cf\u30fc\u30c9\u30a6\u30a7\u30a2\u306e\u518d\u8d77\u52d5<\/a><\/li>\n\n\n\n<li><a href=\"#switch-dns\">\u30b9\u30c6\u30c3\u30d73: \u3088\u308a\u901f\u3044DNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306b\u5207\u308a\u66ff\u3048\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#flush\">\u30b9\u30c6\u30c3\u30d74: DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u30af\u30ea\u30a2\u3059\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#ipv6\">\u30b9\u30c6\u30c3\u30d75: IPv6\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u9045\u5ef6\u3092\u4fee\u6b63\u3059\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#vpn\">\u30b9\u30c6\u30c3\u30d76: VPN\u3001\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\u3001\u30b4\u30fc\u30b9\u30c8\u30a2\u30c0\u30d7\u30bf\u30fc\u3092\u78ba\u8a8d\u3059\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#doh\">\u30b9\u30c6\u30c3\u30d77: DNS over HTTPS\uff08DoH\uff09\u3092\u8a2d\u5b9a\u3059\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#local-cache\">\u30b9\u30c6\u30c3\u30d78: \u30ed\u30fc\u30ab\u30ebDNS\u30ad\u30e3\u30c3\u30b7\u30e5\u30b5\u30fc\u30d0\u30fc\u3092\u5b9f\u884c\u3059\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#browser\">\u30b9\u30c6\u30c3\u30d79: \u30d6\u30e9\u30a6\u30b6\u56fa\u6709\u306eDNS\u554f\u984c\u3092\u4fee\u6b63\u3059\u308b<\/a><\/li>\n\n\n\n<li><a href=\"#optimize-records\">\u30b9\u30c6\u30c3\u30d710: DNS\u30ec\u30b3\u30fc\u30c9\u3092\u6700\u9069\u5316\u3059\u308b\uff08\u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u6240\u6709\u8005\u5411\u3051\uff09<\/a><\/li>\n\n\n\n<li><a href=\"#reduce-domains\">\u30b9\u30c6\u30c3\u30d711: \u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u30c9\u30e1\u30a4\u30f3\u3092\u6e1b\u3089\u3059\uff08\u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u6240\u6709\u8005\u5411\u3051\uff09<\/a><\/li>\n\n\n\n<li><a href=\"#prefetch\">\u30b9\u30c6\u30c3\u30d712: DNS\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1\u3092\u5b9f\u88c5\u3059\u308b\uff08\u30a6\u30a7\u30d6\u958b\u767a\u8005\u5411\u3051\uff09<\/a><\/li>\n\n\n\n<li><a href=\"#troubleshooting\">\u30af\u30a4\u30c3\u30af\u30ea\u30d5\u30a1\u30ec\u30f3\u30b9\u306e\u30c8\u30e9\u30d6\u30eb\u30b7\u30e5\u30fc\u30c6\u30a3\u30f3\u30b0\u8868<\/a><\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n<h2 class=\"wp-block-heading\" id=\"causes\">\u9045\u3044DNS\u306e\u539f\u56e0<\/h2>\n\n\n<p>DNS\u9045\u5ef6\u306b\u5bc4\u4e0e\u3059\u308b\u8981\u56e0\u306f\u3044\u304f\u3064\u304b\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u9045\u3044ISP\u63d0\u4f9b\u306eDNS\u30b5\u30fc\u30d0\u30fc<\/strong> \u2014 ISP\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u30ea\u30be\u30eb\u30d0\u30fc\u306f\u3001\u516c\u5171\u306e\u4ee3\u66ff\u624b\u6bb5\u3088\u308a\u3082\u5927\u5e45\u306b\u9045\u3044\u3053\u3068\u304c\u591a\u3044\u3067\u3059\u3002GoDaddy\u3084Namecheap\u306e\u3088\u3046\u306a\u30ec\u30b8\u30b9\u30c8\u30e9\u304b\u3089\u306e\u7121\u6599DNS\u3082\u901a\u5e38\u9045\u3044\u3067\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u5730\u7406\u7684\u8ddd\u96e2<\/strong> \u2014 DNS\u30b5\u30fc\u30d0\u30fc\u304c\u9060\u304f\u306b\u3042\u308b\u307b\u3069\u3001\u5f80\u5fa9\u306b\u6642\u9593\u304c\u304b\u304b\u308a\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>IPv6\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u9045\u5ef6<\/strong> \u2014 \u73fe\u4ee3\u306e\u30aa\u30da\u30ec\u30fc\u30c6\u30a3\u30f3\u30b0\u30b7\u30b9\u30c6\u30e0\u306fIPv6\uff08AAAA\uff09\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u512a\u5148\u3057\u307e\u3059\u3002ISP\u304cIPv6\u30b5\u30dd\u30fc\u30c8\u306b\u4e4f\u3057\u3044\u5834\u5408\u3001\u30c7\u30d0\u30a4\u30b9\u306fIPv4\u306b\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u3059\u308b\u524d\u306b\u6700\u59275\u79d2\u9593\u30cf\u30f3\u30b0\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u904e\u5270\u306aDNS\u30ec\u30b3\u30fc\u30c9<\/strong> \u2014 \u672a\u4f7f\u7528\u307e\u305f\u306f\u53e4\u3044A\u3001CNAME\u3001\u304a\u3088\u3073TXT\u30ec\u30b3\u30fc\u30c9\u306f\u3001\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u306b\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>CNAME\u30c1\u30a7\u30a4\u30f3<\/strong> \u2014 \u8907\u6570\u306e\u30ea\u30c0\u30a4\u30ec\u30af\u30c8\uff08CNAME \u2192 CNAME \u2192 A\u30ec\u30b3\u30fc\u30c9\uff09\u306f\u3001\u9045\u5ef6\u3092\u7a4d\u307f\u91cd\u306d\u308b\u9010\u6b21\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u5f37\u5236\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u306a\u3057<\/strong> \u2014 \u30ad\u30e3\u30c3\u30b7\u30e5\u304c\u306a\u3044\u3068\u3001\u540c\u3058DNS\u30af\u30a8\u30ea\u304c\u6bce\u56de\u30da\u30fc\u30b8\u30ed\u30fc\u30c9\u6642\u306b\u7e70\u308a\u8fd4\u3055\u308c\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u904e\u8ca0\u8377\u306e\u30cd\u30fc\u30e0\u30b5\u30fc\u30d0\u30fc<\/strong> \u2014 \u904e\u5c11\u30d7\u30ed\u30d3\u30b8\u30e7\u30cb\u30f3\u30b0\u3055\u308c\u305f\u30cd\u30fc\u30e0\u30b5\u30fc\u30d0\u30fc\u3092\u6301\u3064\u30db\u30b9\u30c6\u30a3\u30f3\u30b0\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306f\u9045\u5ef6\u3092\u5f15\u304d\u8d77\u3053\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u6df7\u96d1\u3068\u975e\u6700\u9069\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0<\/strong> \u2014 \u8fd1\u304f\u306e\u30b5\u30fc\u30d0\u30fc\u3067\u3082\u3001\u5230\u9054\u3059\u308b\u7d4c\u8def\u304c\u6df7\u96d1\u3057\u3066\u3044\u308b\u3068\u9045\u304f\u306a\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>VPN\u3068\u30d7\u30ed\u30ad\u30b7\u306e\u5e72\u6e09<\/strong> \u2014 VPN\u306fDNS\u3092\u81ea\u5206\u306e\u30b5\u30fc\u30d0\u30fc\u3092\u901a\u3057\u3066\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3059\u308b\u305f\u3081\u3001\u9045\u304f\u306a\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u4e00\u90e8\u306f\u30c8\u30f3\u30cd\u30eb\u5916\u306bDNS\u30af\u30a8\u30ea\u3092\u6f0f\u3089\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30b4\u30fc\u30b9\u30c8\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc<\/strong> \u2014 VPN\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\u3001\u4eee\u60f3\u30de\u30b7\u30f3\u3001\u307e\u305f\u306fDocker\u304b\u3089\u306e\u30d5\u30a1\u30f3\u30c8\u30e0\u30a2\u30c0\u30d7\u30bf\u30fc\u306f\u3001\u89e3\u6c7a\u3092\u59a8\u3052\u308b\u53e4\u3044DNS\u8a2d\u5b9a\u3092\u4fdd\u6301\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\/\u30d5\u30a1\u30a4\u30a2\u30a6\u30a9\u30fc\u30eb\u306eDNS\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0<\/strong> \u2014 \u4e00\u90e8\u306e\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\uff08Norton\u3001Kaspersky\u3001Bitdefender\uff09\u306fDNS\u30af\u30a8\u30ea\u3092\u508d\u53d7\u3057\u3001\u9045\u5ef6\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30d6\u30e9\u30a6\u30b6\u30ec\u30d9\u30eb\u306eDNS\u30aa\u30fc\u30d0\u30fc\u30e9\u30a4\u30c9<\/strong> \u2014 Chrome\u3001Firefox\u3001Edge\u306f\u3001\u72ec\u81ea\u306e\u7d44\u307f\u8fbc\u307fDNS over HTTPS\uff08DoH\uff09\u8a2d\u5b9a\u3067OS\u306eDNS\u8a2d\u5b9a\u3092\u9759\u304b\u306b\u30aa\u30fc\u30d0\u30fc\u30e9\u30a4\u30c9\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u30c9\u30e1\u30a4\u30f3\u304c\u591a\u3059\u304e\u308b<\/strong> \u2014 \u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u304c\u8aad\u307f\u8fbc\u3080\u5404\u30e6\u30cb\u30fc\u30af\u30c9\u30e1\u30a4\u30f3\u306f\u3001\u7dcf\u30da\u30fc\u30b8\u30ed\u30fc\u30c9\u6642\u9593\u306b\u8ffd\u52a0\u3055\u308c\u308b\u5225\u306eDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u5fc5\u8981\u3068\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30bb\u30ab\u30f3\u30c0\u30eaDNS\u304c\u8a2d\u5b9a\u3055\u308c\u3066\u3044\u306a\u3044<\/strong> \u2014 \u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30afDNS\u30b5\u30fc\u30d0\u30fc\u304c\u306a\u3044\u3068\u3001\u30d7\u30e9\u30a4\u30de\u30ea\u304c\u30c0\u30a6\u30f3\u307e\u305f\u306f\u9045\u3044\u5834\u5408\u3001\u30b7\u30b9\u30c6\u30e0\u306f\u30bf\u30a4\u30e0\u30a2\u30a6\u30c8\u3092\u5f85\u3063\u3066\u30cf\u30f3\u30b0\u3057\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h2 class=\"wp-block-heading\" id=\"diagnose\">\u30b9\u30c6\u30c3\u30d71: \u554f\u984c\u306e\u8a3a\u65ad<\/h2>\n\n\n<p>\u4f55\u304b\u3092\u4fee\u6b63\u3059\u308b\u524d\u306b\u3001DNS\u304c\u5b9f\u969b\u306b\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u3067\u3042\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"using-dig-linuxmacos\">dig\u3092\u4f7f\u7528\u3059\u308b\uff08Linux\/macOS\uff09<\/h3>\n\n\n<p>\u306b\u3064\u3044\u3066 <code>\u6398\u308b<\/code> \u30b3\u30de\u30f3\u30c9\u306fDNS\u5fdc\u7b54\u6642\u9593\u3092\u6e2c\u5b9a\u3059\u308b\u305f\u3081\u306e\u4e3b\u8981\u306a\u30c4\u30fc\u30eb\u3067\u3059\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp># \u7279\u5b9a\u306eDNS\u30b5\u30fc\u30d0\u30fc\u3092\u30af\u30a8\u30ea\u3057\u3001\u5fdc\u7b54\u6642\u9593\u3092\u78ba\u8a8d\u3059\u308b<br>\u6398\u308b example.com @8.8.8.8<br><br># \u5404\u30db\u30c3\u30d7\u306e\u9045\u5ef6\u3092\u793a\u3059\u5b8c\u5168\u306a\u53cd\u5fa9\u30c8\u30ec\u30fc\u30b9<br>\u6398\u308b example.com +trace<\/samp><\/p>\n<\/blockquote>\n\n\n\n<p>\u51fa\u529b\u306b\u306f <code>\u30af\u30a8\u30ea\u6642\u9593<\/code> \u30d5\u30a3\u30fc\u30eb\u30c9\uff08\u4f8b\uff1a34\u30df\u30ea\u79d2\uff09\u304c\u542b\u307e\u308c\u307e\u3059\u3002\u3053\u308c\u304c100\u30df\u30ea\u79d2\u3092\u8d85\u3048\u308b\u5834\u5408\u3001DNS\u30ec\u30a4\u30e4\u30fc\u304c\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u554f\u984c\u3067\u3059\u3002\u7406\u60f3\u7684\u306b\u306f50\u30df\u30ea\u79d2\u672a\u6e80\u3092\u76ee\u6307\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"using-nslookup-windows\">nslookup\u3092\u4f7f\u7528\u3059\u308b\uff08Windows\uff09<\/h3>\n\n\n<p>Windows\u30e6\u30fc\u30b6\u30fc\u5411\u3051\u306b\u3001, <code>nslookup<\/code> \u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u306eDNS\u8a3a\u65ad\u30c4\u30fc\u30eb\u3067\u3059\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp># \u57fa\u672c\u7684\u306aDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7<br>nslookup example.com<br><br># \u7279\u5b9a\u306eDNS\u30b5\u30fc\u30d0\u30fc\u3092\u30af\u30a8\u30ea\u3059\u308b<br>nslookup example.com 8.8.8.8<br><br># \u30c9\u30e1\u30a4\u30f3\u306e\u30cd\u30fc\u30e0\u30b5\u30fc\u30d0\u30fc\u3092\u78ba\u8a8d\u3059\u308b<br>nslookup -type=ns example.com<\/samp><\/p>\n<\/blockquote>\n\n\n\n<p>\u3082\u3057 <code>nslookup<\/code> \u7d50\u679c\u304c\u3059\u3050\u306b\u8fd4\u3063\u3066\u304f\u308b\u304c\u30d6\u30e9\u30a6\u30b8\u30f3\u30b0\u304c\u9045\u3044\u3068\u611f\u3058\u308b\u5834\u5408\u3001\u554f\u984c\u306f\u30d6\u30e9\u30a6\u30b6\u30ec\u30d9\u30eb\u306eDNS\u3001IPv6\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u3001\u307e\u305f\u306fVPN\u306e\u5e72\u6e09\u3067\u3042\u308a\u3001DNS\u30b5\u30fc\u30d0\u30fc\u81ea\u4f53\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"using-ping-and-traceroute\">ping\u3068traceroute\u3092\u4f7f\u7528\u3059\u308b<\/h3>\n\n\n<p>DNS\u30b5\u30fc\u30d0\u30fc\u3078\u306e\u751f\u306e\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u9045\u5ef6\u3092\u30c6\u30b9\u30c8\u3057\u3066\u3001\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u306e\u554f\u984c\u3092DNS\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u554f\u984c\u304b\u3089\u5206\u96e2\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp># Linux\/macOS<br>ping -c 3 8.8.8.8<br>\u30c8\u30ec\u30fc\u30b9\u30eb\u30fc\u30c8 8.8.8.8<br><br># Windows<br>ping 8.8.8.8<br>tracert 8.8.8.8<\/samp><\/p>\n<\/blockquote>\n\n\n\n<p>\u3082\u3057ping\u304c\u9ad8\u3044\u9045\u5ef6\u3092\u793a\u3057\u3066\u3044\u308b\u304c\u3001 <code>\u6398\u308b<\/code> \u540c\u3058\u30b5\u30fc\u30d0\u30fc\u3078\u306e\u9045\u5ef6\u304c\u6bd4\u4f8b\u3057\u3066\u9045\u3044\u5834\u5408\u3001\u554f\u984c\u306f\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u8ddd\u96e2\u3067\u3042\u308a\u3001DNS\u30b5\u30fc\u30d0\u30fc\u81ea\u4f53\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"350\" src=\"https:\/\/securitybriefing.net\/wp-content\/uploads\/2026\/02\/Slow-DNS-Lookup.jpg\" alt=\"DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u304c\u9045\u3044\" class=\"wp-image-5246\" srcset=\"https:\/\/securitybriefing.net\/wp-content\/uploads\/2026\/02\/Slow-DNS-Lookup.jpg 600w, https:\/\/securitybriefing.net\/wp-content\/uploads\/2026\/02\/Slow-DNS-Lookup-300x175.jpg 300w, https:\/\/securitybriefing.net\/wp-content\/uploads\/2026\/02\/Slow-DNS-Lookup-18x12.jpg 18w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"dns-benchmark-tools\">DNS\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u30c4\u30fc\u30eb<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>GRC DNS \u30d9\u30f3\u30c1\u30de\u30fc\u30af<\/strong> \u2014 Windows\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u3067\u3001\u6570\u5341\u306eDNS\u30b5\u30fc\u30d0\u30fc\u3092\u30c6\u30b9\u30c8\u3057\u3001\u3042\u306a\u305f\u306e\u5834\u6240\u304b\u3089\u306e\u901f\u5ea6\u3067\u30e9\u30f3\u30af\u4ed8\u3051\u3057\u307e\u3059\u3002\u7279\u5b9a\u306e\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u306b\u6700\u9069\u306a\u30ea\u30be\u30eb\u30d0\u30fc\u3092\u898b\u3064\u3051\u308b\u305f\u3081\u306b\u975e\u5e38\u306b\u63a8\u5968\u3055\u308c\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30cd\u30fc\u30e0\u30d9\u30f3\u30c1<\/strong> \u2014 Google\u6240\u6709\u306e\u30c4\u30fc\u30eb\u3067\u3001\u30b3\u30f3\u30d4\u30e5\u30fc\u30bf\u306b\u5229\u7528\u53ef\u80fd\u306a\u6700\u901f\u306eDNS\u30b5\u30fc\u30d0\u30fc\u3092\u63a2\u3057\u51fa\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>DNSPerf<\/strong> \u2014 \u8ca0\u8377\u4e0b\u3067\u306e\u6a29\u5a01\u3042\u308bDNS\u30b5\u30fc\u30d0\u30fc\u306e\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u3092\u884c\u3046\u30aa\u30fc\u30d7\u30f3\u30bd\u30fc\u30b9\u30c4\u30fc\u30eb\u3067\u3059\u3002.<\/li>\n\n\n\n<li><strong>dnsdiag\uff08dnsping\u3001dnstraceroute\u3001dnseval\uff09<\/strong> \u2014 DNS\u6e2c\u5b9a\u7528\u306ePython\u30c4\u30fc\u30eb\u30bb\u30c3\u30c8\u3067\u3059\u3002 <code>pip3 install dnsdiag<\/code>.<\/li>\n\n\n\n<li><strong>dnsspeedtest.site<\/strong> \u2014 \u30d6\u30e9\u30a6\u30b6\u30d9\u30fc\u30b9\u306e\u30c4\u30fc\u30eb\u3067\u3001\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\u3092\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u305b\u305a\u306bDNS over HTTPS\u3092\u4f7f\u7528\u3057\u306620\u4ee5\u4e0a\u306eDNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u3092\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u3057\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h2 class=\"wp-block-heading\" id=\"restart\">\u30b9\u30c6\u30c3\u30d72: \u30cf\u30fc\u30c9\u30a6\u30a7\u30a2\u306e\u518d\u8d77\u52d5<\/h2>\n\n\n<p>\u3088\u304f\u898b\u904e\u3054\u3055\u308c\u308b\u6700\u3082\u7c21\u5358\u306a\u4fee\u6b63\u3067\u3059\u3002\u30eb\u30fc\u30bf\u30fc\u3092\u518d\u8d77\u52d5\u3059\u308b\u3068\u3001\u5185\u90e8DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u304c\u30af\u30ea\u30a2\u3055\u308c\u3001\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u306e\u554f\u984c\u304c\u89e3\u6c7a\u3055\u308c\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u591a\u304f\u306eISP\u30eb\u30fc\u30bf\u30fc\u306b\u306f\u3001\u6642\u9593\u3068\u3068\u3082\u306b\u904e\u8ca0\u8377\u307e\u305f\u306f\u53e4\u304f\u306a\u308b\u53ef\u80fd\u6027\u306e\u3042\u308b\u7d44\u307f\u8fbc\u307f\u306eDNS\u30d5\u30a9\u30ef\u30fc\u30c0\u30fc\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30eb\u30fc\u30bf\u30fc\u306e\u96fb\u6e90\u309230\u79d2\u9593\u629c\u3044\u3066\u304b\u3089\u3001\u518d\u63a5\u7d9a\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li>PC\u3001\u96fb\u8a71\u3001\u307e\u305f\u306f\u30bf\u30d6\u30ec\u30c3\u30c8\u3092\u518d\u8d77\u52d5\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li>\u5225\u306e\u30e2\u30c7\u30e0\u3092\u4f7f\u7528\u3057\u3066\u3044\u308b\u5834\u5408\u3001\u305d\u308c\u3082\u518d\u8d77\u52d5\u3057\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u306b\u3088\u308a\u3001\u4e00\u6642\u7684\u306a\u4e0d\u5177\u5408\u304c\u30af\u30ea\u30a2\u3055\u308c\u3001\u65b0\u3057\u3044DNS\u63a5\u7d9a\u304c\u5f37\u5236\u3055\u308c\u307e\u3059\u3002\u4ed6\u306e\u4fee\u6b63\u3092\u8a66\u307f\u308b\u524d\u306b\u3053\u308c\u3092\u8a66\u3057\u3066\u304f\u3060\u3055\u3044\u3002.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"switch-dns\">\u30b9\u30c6\u30c3\u30d73: \u3088\u308a\u901f\u3044DNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306b\u5207\u308a\u66ff\u3048\u308b<\/h2>\n\n\n<p>\u3053\u308c\u306f\u307b\u3068\u3093\u3069\u306e\u30e6\u30fc\u30b6\u30fc\u306b\u3068\u3063\u3066\u6700\u3082\u5f71\u97ff\u529b\u306e\u3042\u308b\u4fee\u6b63\u3067\u3059\u3002ISP\u306e\u30c7\u30d5\u30a9\u30eb\u30c8DNS\u3092\u3088\u308a\u901f\u3044\u516c\u5171\u306e\u30ea\u30be\u30eb\u30d0\u30fc\u306b\u7f6e\u304d\u63db\u3048\u307e\u3059\u3002\u5e38\u306b\u30d7\u30e9\u30a4\u30de\u30ea\u3068\u30bb\u30ab\u30f3\u30c0\u30ea\u306e\u4e21\u65b9\u306eDNS\u3092\u8a2d\u5b9a\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u304c\u306a\u3044\u3068\u3001\u30d7\u30e9\u30a4\u30de\u30ea\u304c\u30c0\u30a6\u30f3\u307e\u305f\u306f\u9045\u3044\u5834\u5408\u3001\u30b7\u30b9\u30c6\u30e0\u306f\u30bf\u30a4\u30e0\u30a2\u30a6\u30c8\u3092\u5f85\u3063\u3066\u30cf\u30f3\u30b0\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th>\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc<\/th><th>\u30d7\u30e9\u30a4\u30de\u30ea<\/th><th>\u30bb\u30ab\u30f3\u30c0\u30ea<\/th><th>\u5f37\u307f<\/th><\/tr><tr><td>\u30af\u30e9\u30a6\u30c9\u30d5\u30ec\u30a2<\/td><td>1.1.1.1<\/td><td>1.0.0.1<\/td><td>\u4e16\u754c\u7684\u306b\u6700\u901f\u3067\u3042\u308b\u3053\u3068\u304c\u591a\u3044; \u5f37\u529b\u306a\u30d7\u30e9\u30a4\u30d0\u30b7\u30fc\u30dd\u30ea\u30b7\u30fc; EDNS\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u30b5\u30d6\u30cd\u30c3\u30c8\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u306a\u3044\uff08\u3088\u308a\u7a4d\u6975\u7684\u306a\u30ad\u30e3\u30c3\u30b7\u30f3\u30b0\uff09\u3002.<\/td><\/tr><tr><td>\u30b0\u30fc\u30b0\u30eb\u30d1\u30d6\u30ea\u30c3\u30afDNS<\/td><td>8.8.8.8<\/td><td>8.8.4.4<\/td><td>\u975e\u5e38\u306b\u4fe1\u983c\u6027\u304c\u9ad8\u3044; \u9ad8\u3044\u7a3c\u50cd\u6642\u9593; \u3088\u308a\u826f\u3044CDN\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u306e\u305f\u3081\u306bEDNS\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u30b5\u30d6\u30cd\u30c3\u30c8\u3092\u30b5\u30dd\u30fc\u30c8\u3002.<\/td><\/tr><tr><td>Quad9<\/td><td>9.9.9.9<\/td><td>149.112.112.112<\/td><td>\u77e5\u3089\u308c\u3066\u3044\u308b\u60aa\u610f\u306e\u3042\u308b\u30c9\u30e1\u30a4\u30f3\u3092\u30d6\u30ed\u30c3\u30af; \u5f37\u529b\u306a\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30d5\u30a9\u30fc\u30ab\u30b9\u3002.<\/td><\/tr><tr><td>\u30aa\u30fc\u30d7\u30f3DNS<\/td><td>208.67.222.222<\/td><td>208.67.220.220<\/td><td>\u9ad8\u901f\u306a\u30af\u30a8\u30ea\u51e6\u7406; \u30b3\u30f3\u30c6\u30f3\u30c4\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u30aa\u30d7\u30b7\u30e7\u30f3; \u30da\u30a2\u30ec\u30f3\u30bf\u30eb\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u3002.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p><strong>Cloudflare\u3068Google\u306e\u6bd4\u8f03\u306b\u95a2\u3059\u308b\u6ce8\u610f:<\/strong> ThousandEyes\u306e\u8abf\u67fb\u306b\u3088\u308b\u3068\u3001Cloudflare\u306fISP\u30b5\u30fc\u30d0\u30fc\u3068\u540c\u7b49\u306eDNS\u89e3\u6c7a\u3092\u63d0\u4f9b\u3057\uff08\u5e73\u574723.4\u30df\u30ea\u79d2\uff09\u3001Google\u306f\u5e73\u574748.8\u30df\u30ea\u79d2\u3067\u3057\u305f\u3002\u3057\u304b\u3057\u3001Google\u306eEDNS\u30af\u30e9\u30a4\u30a2\u30f3\u30c8\u30b5\u30d6\u30cd\u30c3\u30c8\u30b5\u30dd\u30fc\u30c8\u306fCDN\u30ad\u30e3\u30c3\u30b7\u30e5\u30d2\u30c3\u30c8\u7387\u3092\u6539\u5584\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u512a\u5148\u9806\u4f4d\u306b\u57fa\u3065\u3044\u3066\u9078\u629e\u3057\u3066\u304f\u3060\u3055\u3044\uff1a\u751f\u306e\u901f\u5ea6\uff08Cloudflare\uff09\u307e\u305f\u306fCDN\u6700\u9069\u5316\uff08Google\uff09\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-change-dns-on-windows\">Windows\u3067\u306eDNS\u306e\u5909\u66f4\u65b9\u6cd5<\/h3>\n\n\n<p>\u8a2d\u5b9a\u3092\u958b\u304f\u2192\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u3068\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u2192\u30a4\u30fc\u30b5\u30cd\u30c3\u30c8\uff08\u307e\u305f\u306fWi-Fi\uff09\u3002DNS\u30b5\u30fc\u30d0\u30fc\u306e\u5272\u308a\u5f53\u3066\u306e\u6a2a\u306b\u3042\u308b\u300c\u7de8\u96c6\u300d\u3092\u30af\u30ea\u30c3\u30af\u3057\u307e\u3059\u3002\u624b\u52d5\u306b\u5207\u308a\u66ff\u3048\u3001IPv4\u3092\u6709\u52b9\u306b\u3057\u3001\u5e0c\u671b\u3059\u308bDNS\u30a2\u30c9\u30ec\u30b9\u3092\u5165\u529b\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p>\u307e\u305f\u306f\u3001\u30b3\u30de\u30f3\u30c9\u30d7\u30ed\u30f3\u30d7\u30c8\u3092\u4f7f\u7528\u3057\u3066\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp>netsh interface ip add dns name=&#8221;Ethernet&#8221; addr=1.1.1.1 index=1<br>netsh interface ip add dns name=&#8221;Ethernet&#8221; addr=1.0.0.1 index=2<\/samp><\/p>\n<\/blockquote>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-change-dns-on-macoslinux\">macOS\/Linux\u3067\u306eDNS\u306e\u5909\u66f4\u65b9\u6cd5<\/h3>\n\n\n<p>macOS\u3067\u306f\u3001\u30b7\u30b9\u30c6\u30e0\u8a2d\u5b9a\u2192\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u2192\u63a5\u7d9a\u2192DNS\u306b\u79fb\u52d5\u3057\u3001\u30ea\u30be\u30eb\u30d0\u30fcIP\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002Linux\u3067\u306f\u3001 <code>\/etc\/resolv.conf<\/code> \u3092\u7de8\u96c6\u3059\u308b\u304b\u3001\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30de\u30cd\u30fc\u30b8\u30e3\u30fc\u3092\u4ecb\u3057\u3066\u8a2d\u5b9a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp># Linux: \/etc\/resolv.conf\u3092\u7de8\u96c6<br>sudo nano \/etc\/resolv.conf<br><br># \u3053\u308c\u3089\u306e\u884c\u3092\u8ffd\u52a0\uff1a<br>nameserver 1.1.1.1<br>nameserver 1.0.0.1<\/samp><\/p>\n<\/blockquote>\n\n\n<h3 class=\"wp-block-heading\" id=\"change-dns-on-your-router\">\u30eb\u30fc\u30bf\u30fc\u3067\u306eDNS\u306e\u5909\u66f4<\/h3>\n\n\n<p>\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u5168\u4f53\u306e\u5909\u66f4\u306e\u305f\u3081\u306b\u3001\u30eb\u30fc\u30bf\u30fc\u306e\u7ba1\u7406\u30d1\u30cd\u30eb\uff08\u901a\u5e38192.168.1.1\u307e\u305f\u306f192.168.0.1\uff09\u3067DNS\u8a2d\u5b9a\u3092\u66f4\u65b0\u3057\u307e\u3059\u3002\u3053\u308c\u306b\u3088\u308a\u3001\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u4e0a\u306e\u3059\u3079\u3066\u306e\u30c7\u30d0\u30a4\u30b9\u306b\u5f71\u97ff\u3092\u4e0e\u3048\u307e\u3059\u2014\u5404\u30c7\u30d0\u30a4\u30b9\u3067\u8a2d\u5b9a\u3059\u308b\u4ee3\u308f\u308a\u306b\u4e00\u5ea6\u3060\u3051\u8a2d\u5b9a\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"flush\">\u30b9\u30c6\u30c3\u30d74: DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u30af\u30ea\u30a2\u3059\u308b<\/h2>\n\n\n<p>\u53e4\u3044\u307e\u305f\u306f\u7834\u640d\u3057\u305f\u30ad\u30e3\u30c3\u30b7\u30e5\u30a8\u30f3\u30c8\u30ea\u306f\u3001\u89e3\u6c7a\u306e\u5931\u6557\u3084\u9593\u9055\u3063\u305fIP\u3078\u306e\u30ea\u30c0\u30a4\u30ec\u30af\u30c8\u3092\u5f15\u304d\u8d77\u3053\u3059\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u30d5\u30e9\u30c3\u30b7\u30e5\u3059\u308b\u3068\u65b0\u3057\u3044\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u304c\u5f37\u5236\u3055\u308c\u307e\u3059\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th>OS<\/th><th>\u30b3\u30de\u30f3\u30c9<\/th><\/tr><tr><td>Windows 10\/11<\/td><td><code>ipconfig \/flushdns<\/code><\/td><\/tr><tr><td>macOS\uff08Ventura+\uff09<\/td><td><code>sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder<\/code><\/td><\/tr><tr><td>Linux\uff08systemd\uff09<\/td><td><code>sudo systemd-resolve --flush-caches<\/code> \u307e\u305f\u306f <code>sudo resolvectl flush-caches<\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>\u30d6\u30e9\u30a6\u30b6\u30ec\u30d9\u30eb\u306e\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u5fd8\u308c\u306a\u3044\u3067\u304f\u3060\u3055\u3044\u3002Chrome\u3067\u306f\u3001 <code>chrome:\/\/net-internals\/#dns<\/code> \u306b\u79fb\u52d5\u3057\u3001\u300c\u30db\u30b9\u30c8\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u30af\u30ea\u30a2\u300d\u3092\u30af\u30ea\u30c3\u30af\u3057\u307e\u3059\u3002Firefox\u3067\u306f\u3001\u30d6\u30e9\u30a6\u30b6\u3092\u518d\u8d77\u52d5\u3059\u308b\u304b\u3001 <code>about:networking#dns<\/code>.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"ipv6\">\u30b9\u30c6\u30c3\u30d75: IPv6\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u9045\u5ef6\u3092\u4fee\u6b63\u3059\u308b<\/h2>\n\n\n<p>\u3067DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u30af\u30ea\u30a2\u3067\u304d\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-diagnose\">\u3053\u308c\u306f\u3001\u6a19\u6e96\u30ac\u30a4\u30c9\u304c\u7121\u8996\u3059\u308b\u6700\u3082\u4e00\u822c\u7684\u306a\u96a0\u308c\u305f\u539f\u56e0\u306e1\u3064\u3067\u3059\u3002\u73fe\u4ee3\u306e\u30aa\u30da\u30ec\u30fc\u30c6\u30a3\u30f3\u30b0\u30b7\u30b9\u30c6\u30e0\u306f\u3001IPv4\u3088\u308a\u3082IPv6\uff08AAAA\uff09\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u512a\u5148\u3057\u307e\u3059\u3002ISP\u304cIPv6\u30b5\u30dd\u30fc\u30c8\u306b\u4e4f\u3057\u3044\u5834\u5408\u3001\u30c7\u30d0\u30a4\u30b9\u306fIPv4\u306b\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u3059\u308b\u524d\u306b\u6700\u59275\u79d2\u9593IPv6\u5fdc\u7b54\u3092\u5f85\u3061\u307e\u3059\u3002\u3053\u308c\u306f\u65b0\u3057\u3044\u63a5\u7d9a\u3054\u3068\u306b\u767a\u751f\u3057\u307e\u3059\u3002<\/h3>\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp>\u8a3a\u65ad\u65b9\u6cd5<br># IPv6\u63a5\u7d9a\u3092\u30c6\u30b9\u30c8\u3059\u308b<br><br>ping -6 google.com<br># \u3053\u308c\u304c\u30bf\u30a4\u30e0\u30a2\u30a6\u30c8\u3059\u308b\u304b\u6570\u79d2\u304b\u304b\u308b\u5834\u5408\u3001IPv6\u304c\u554f\u984c\u3067\u3059<br># IPv4\u3068\u6bd4\u8f03\u3059\u308b\uff1a<\/samp><\/p>\n<\/blockquote>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-fix\">ping -4 google.com<\/h3>\n\n\n<p><strong>\u4fee\u6b63\u65b9\u6cd5<\/strong> \u30aa\u30d7\u30b7\u30e7\u30f31: \u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc\u3067IPv6\u3092\u7121\u52b9\u306b\u3059\u308b<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\uff08ISP\u304c\u30b5\u30dd\u30fc\u30c8\u3057\u3066\u3044\u306a\u3044\u5834\u5408\uff09\u201c<\/li>\n\n\n\n<li>Windows: \u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc\u306e\u30d7\u30ed\u30d1\u30c6\u30a3\u2192\u300c\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u30d7\u30ed\u30c8\u30b3\u30eb\u30d0\u30fc\u30b8\u30e7\u30f36\uff08TCP\/IPv6\uff09\u300d\u306e\u30c1\u30a7\u30c3\u30af\u3092\u5916\u3059 <code>Linux:<\/code> \u3078 <code>\/etc\/sysctl.conf<\/code><\/li>\n\n\n\n<li>\u306b<\/li>\n<\/ul>\n\n\n\n<p><strong>net.ipv6.conf.all.disable_ipv6 = 1<\/strong> \u3092\u8ffd\u52a0 <code>macOS: \u30b7\u30b9\u30c6\u30e0\u8a2d\u5b9a\u2192\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u2192\u63a5\u7d9a\u2192TCP\/IP\u2192IPv6\u3092\u69cb\u6210\u2192\u30ea\u30f3\u30af\u30ed\u30fc\u30ab\u30eb\u306e\u307f<\/code> \u30aa\u30d7\u30b7\u30e7\u30f32: IPv4\u3092\u512a\u5148\u3059\u308b <code>IPv6\u3092\u5b8c\u5168\u306b\u7121\u52b9\u306b\u305b\u305a\u306b\u2014Linux\u3067\u306f\u3001<\/code>.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"vpn\">\u30b9\u30c6\u30c3\u30d76: VPN\u3001\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\u3001\u30b4\u30fc\u30b9\u30c8\u30a2\u30c0\u30d7\u30bf\u30fc\u3092\u78ba\u8a8d\u3059\u308b<\/h2>\n\n<h3 class=\"wp-block-heading\" id=\"vpn-and-proxy-dns-interference\">\/etc\/gai.conf<\/h3>\n\n\n<p>\u3092\u7de8\u96c6\u3057\u3001<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>precedence ::ffff:0:0\/96 100 <strong>\u3092\u30b3\u30e1\u30f3\u30c8\u89e3\u9664<\/strong> VPN\u3068\u30d7\u30ed\u30ad\u30b7\u306eDNS\u5e72\u6e09.<\/li>\n\n\n\n<li>VPN\u306f\u3057\u3070\u3057\u3070DNS\u3092\u81ea\u5206\u306e\u30b5\u30fc\u30d0\u30fc\u3092\u901a\u3057\u3066\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3057\u3001\u5730\u5143\u306e\u30ea\u30be\u30eb\u30d0\u30fc\u3088\u308a\u3082\u9045\u304f\u306a\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u4e00\u90e8\u306eVPN\u306f\u30c8\u30f3\u30cd\u30eb\u5916\u306bDNS\u30af\u30a8\u30ea\u3092\u6f0f\u3089\u3057\u3001\u4e0d\u5b89\u5b9a\u306a\u52d5\u4f5c\u3092\u5f15\u304d\u8d77\u3053\u3057\u307e\u3059\u3002\u8a3a\u65ad\u3059\u308b\u306b\u306f\uff1a.<\/li>\n\n\n\n<li>VPN\u306b\u63a5\u7d9a\u3057\u3066\u3044\u308b\u9593\u306b.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"antivirus-firewall-dns-filtering\">dnsleaktest.com<\/h3>\n\n\n<p>\u3092\u8a2a\u554f\u3057\u3001DNS\u30ea\u30fc\u30af\u3092\u78ba\u8a8d\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e00\u6642\u7684\u306bVPN\u3092\u5207\u65ad\u3057\u3001DNS\u901f\u5ea6\u3092\u30c6\u30b9\u30c8\u3057\u307e\u3059\u3002VPN\u306a\u3057\u3067\u901f\u3044\u5834\u5408\u3001VPN\u306eDNS\u304c\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u3067\u3059\u3002.<\/li>\n\n\n\n<li>\u591a\u304f\u306eVPN\u306f\u30ab\u30b9\u30bf\u30e0DNS\u30b5\u30fc\u30d0\u30fc\u306e\u8a2d\u5b9a\u3092\u8a31\u53ef\u3057\u3066\u3044\u307e\u3059\u2014VPN\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306eDNS\u306e\u4ee3\u308f\u308a\u306bCloudflare\u3084Google\u3092\u4f7f\u7528\u3057\u3066\u304f\u3060\u3055\u3044\u3002.<\/li>\n\n\n\n<li>\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\/\u30d5\u30a1\u30a4\u30a2\u30a6\u30a9\u30fc\u30eb\u306eDNS\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"ghost-network-adapters\">\u4e00\u90e8\u306e\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\uff08Norton\u3001Kaspersky\u3001Bitdefender\uff09\u306fDNS\u30af\u30a8\u30ea\u3092\u508d\u53d7\u3057\u3001\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u3059\u308b\u3053\u3068\u3067\u9045\u5ef6\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30d5\u30a1\u30a4\u30a2\u30a6\u30a9\u30fc\u30eb\u3082\u672a\u77e5\u306e\u30b5\u30fc\u30d0\u30fc\u3078\u306eDNS\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\u3092\u30d6\u30ed\u30c3\u30af\u307e\u305f\u306f\u30b9\u30ed\u30c3\u30c8\u30eb\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u30c6\u30b9\u30c8\u3059\u308b\u306b\u306f\uff1a<\/h3>\n\n\n<p>\u4e00\u6642\u7684\u306b\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\u306e\u30a6\u30a7\u30d6\u4fdd\u8b77\u3092\u7121\u52b9\u306b\u3057\u3001DNS\u901f\u5ea6\u3092\u30c6\u30b9\u30c8\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p>\u30d5\u30a1\u30a4\u30a2\u30a6\u30a9\u30fc\u30eb\u30eb\u30fc\u30eb\u3067DNS\u95a2\u9023\u306e\u30d6\u30ed\u30c3\u30af\uff08\u30a2\u30a6\u30c8\u30d0\u30a6\u30f3\u30c9\u30dd\u30fc\u30c853\u307e\u305f\u306f853\uff09\u304c\u306a\u3044\u304b\u78ba\u8a8d\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp>\u30a2\u30f3\u30c1\u30a6\u30a4\u30eb\u30b9\u3092\u7121\u52b9\u306b\u3057\u3066DNS\u304c\u901f\u304f\u306a\u308b\u5834\u5408\u3001\u5e0c\u671b\u3059\u308bDNS\u30b5\u30fc\u30d0\u30fc\u306e\u4f8b\u5916\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002<br>\u30b4\u30fc\u30b9\u30c8\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc<br>\u53e4\u3044\u307e\u305f\u306f\u30d5\u30a1\u30f3\u30c8\u30e0\u306e\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc\u306f\u3001VPN\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\u3001\u4eee\u60f3\u30de\u30b7\u30f3\uff08VMware\u3001VirtualBox\uff09\u3001\u307e\u305f\u306fDocker\u304b\u3089\u306e\u3082\u306e\u3067\u3001\u89e3\u6c7a\u3092\u59a8\u3052\u308b\u53e4\u3044DNS\u8a2d\u5b9a\u3092\u4fdd\u6301\u3057\u307e\u3059\u3002\u7279\u306bWindows\u3067\u3053\u306e\u554f\u984c\u304c\u767a\u751f\u3057\u3084\u3059\u3044\u3067\u3059\u3002<br>Windows\u3067\u4fee\u6b63\u3059\u308b\u306b\u306f\uff1a<br><br># \u30c7\u30d0\u30a4\u30b9\u30de\u30cd\u30fc\u30b8\u30e3\u30fc\u3067\u96a0\u3057\u30c7\u30d0\u30a4\u30b9\u3092\u8868\u793a\u3059\u308b<br># \u7ba1\u7406\u8005\u3068\u3057\u3066CMD\u3092\u958b\u304f\uff1a<\/samp><\/p>\n<\/blockquote>\n\n\n<h2 class=\"wp-block-heading\" id=\"doh\">\u30b9\u30c6\u30c3\u30d77: DNS over HTTPS\uff08DoH\uff09\u3092\u8a2d\u5b9a\u3059\u308b<\/h2>\n\n\n<p>set devmgr_show_nonpresent_devices=1.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"benefits\">devmgmt.msc<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li># \u30c7\u30d0\u30a4\u30b9\u30de\u30cd\u30fc\u30b8\u30e3\u30fc\u3067\uff1a\u8868\u793a\u2192\u96a0\u3057\u30c7\u30d0\u30a4\u30b9\u3092\u8868\u793a.<\/li>\n\n\n\n<li># \u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc\u306e\u4e0b\u3067\u3001\u7070\u8272\u306e\/\u30d5\u30a1\u30f3\u30c8\u30e0\u30a2\u30c0\u30d7\u30bf\u30fc\u3092\u524a\u9664\u3059\u308b.<\/li>\n\n\n\n<li>DNS over HTTPS\uff08DoH\uff09\u306f\u3001DNS\u30af\u30a8\u30ea\u3092HTTPS\u5185\u3067\u6697\u53f7\u5316\u3057\u3001ISP\u306e\u30b9\u30cc\u30fc\u30d4\u30f3\u30b0\u3001DNS\u30b9\u30d7\u30fc\u30d5\u30a3\u30f3\u30b0\u3001\u304a\u3088\u3073\u4e2d\u9593\u8005\u653b\u6483\u3092\u9632\u304e\u307e\u3059\u3002\u3057\u304b\u3057\u3001\u8aa4\u3063\u3066\u69cb\u6210\u3055\u308c\u308b\u3068\u554f\u984c\u3092\u5f15\u304d\u8d77\u3053\u3059\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"potential-issues\">\u5229\u70b9<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>DNS\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\u3092\u6697\u53f7\u5316\u3059\u308b\u2014ISP\u3084\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u7ba1\u7406\u8005\u306fDNS\u30af\u30a8\u30ea\u3092\u898b\u3089\u308c\u307e\u305b\u3093\u3002<\/strong> DNS\u30b9\u30d7\u30fc\u30d5\u30a3\u30f3\u30b0\u3068\u30ad\u30e3\u30c3\u30b7\u30e5\u30dd\u30a4\u30ba\u30cb\u30f3\u30b0\u653b\u6483\u3092\u9632\u304e\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u6a19\u6e96HTTPS\uff08\u30dd\u30fc\u30c8443\uff09\u3092\u4f7f\u7528\u3059\u308b\u305f\u3081\u3001\u30d5\u30a1\u30a4\u30a2\u30a6\u30a9\u30fc\u30eb\u306b\u3088\u3063\u3066\u30d6\u30ed\u30c3\u30af\u3055\u308c\u308b\u3053\u3068\u306f\u307b\u3068\u3093\u3069\u3042\u308a\u307e\u305b\u3093\u3002<\/strong> \u6f5c\u5728\u7684\u306a\u554f\u984c.<\/li>\n\n\n\n<li><strong>\u9045\u5ef6\u306e\u8ffd\u52a0\uff1a<\/strong> HTTPS\/TLS\u30cf\u30f3\u30c9\u30b7\u30a7\u30a4\u30af\u304c\u6700\u521d\u306e\u63a5\u7d9a\u306b\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u5f8c\u7d9a\u306e\u30af\u30a8\u30ea\u306f\u63a5\u7d9a\u306e\u518d\u5229\u7528\u306b\u3088\u308a\u901f\u304f\u306a\u308a\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u30ed\u30fc\u30ab\u30ebDNS\u30d5\u30a3\u30eb\u30bf\u3068\u306e\u7af6\u5408\uff1a<\/strong> DoH\u306fPi-hole\u3001\u30ed\u30fc\u30ab\u30ebDNS\u30b5\u30fc\u30d0\u30fc\u3001\u30da\u30a2\u30ec\u30f3\u30bf\u30eb\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u3092\u30d0\u30a4\u30d1\u30b9\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>VPN\u3068\u306e\u7af6\u5408\uff1a<\/strong> DoH\u304c\u6b63\u3057\u304f\u69cb\u6210\u3055\u308c\u3066\u3044\u306a\u3044\u5834\u5408\u3001DNS\u3092VPN\u30c8\u30f3\u30cd\u30eb\u5916\u306b\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-enable-doh\">\u30b9\u30d7\u30ea\u30c3\u30c8DNS\u306e\u554f\u984c\uff1a<\/h3>\n\n\n<p><strong>\u5185\u90e8\u30ea\u30bd\u30fc\u30b9\u7528\u306b\u5185\u90e8DNS\u3092\u4f7f\u7528\u3059\u308b\u4f01\u696d\u74b0\u5883\u3067\u306f\u3001DoH\u304c\u6709\u52b9\u306b\u306a\u308b\u3068\u554f\u984c\u304c\u767a\u751f\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002<\/strong> \u30d6\u30e9\u30a6\u30b6\u306e\u30aa\u30fc\u30d0\u30fc\u30e9\u30a4\u30c9\uff1a\u201c<\/p>\n\n\n\n<p><strong>Chrome\u3001Firefox\u3001Edge\u306b\u306f\u3001OS\u306eDNS\u8a2d\u5b9a\u3092\u9759\u304b\u306b\u30aa\u30fc\u30d0\u30fc\u30e9\u30a4\u30c9\u3059\u308b\u7d44\u307f\u8fbc\u307f\u306eDoH\u304c\u3042\u308a\u307e\u3059\u3002<\/strong> DoH\u3092\u6709\u52b9\u306b\u3059\u308b\u65b9\u6cd5.<\/p>\n\n\n\n<p><strong>Windows 11\uff1a<\/strong> \u8a2d\u5b9a\u2192\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u2192\u30a4\u30fc\u30b5\u30cd\u30c3\u30c8\/ Wi-Fi\u2192DNS\u2192\u300c\u512a\u5148DNS\u6697\u53f7\u5316\u300d\u3092\u300c\u6697\u53f7\u5316\u306e\u307f\uff08DNS over HTTPS\uff09\u300d\u307e\u305f\u306f\u300c\u6697\u53f7\u5316\u512a\u5148\u3001\u975e\u6697\u53f7\u5316\u8a31\u53ef\u300d\u306b\u8a2d\u5b9a\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-disable-doh-when-troubleshooting\">Chrome\/Edge\uff1a<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li>\u8a2d\u5b9a\u2192\u30d7\u30e9\u30a4\u30d0\u30b7\u30fc\u2192\u300c\u5b89\u5168\u306aDNS\u3092\u4f7f\u7528\u3059\u308b\u300d\u2192\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u3092\u9078\u629e\uff08Cloudflare\u3001Google\u306a\u3069\uff09\u3002\u201c<\/li>\n\n\n\n<li>Chrome\/Edge: \u300c\u30bb\u30ad\u30e5\u30a2DNS\u3092\u4f7f\u7528\u3059\u308b\u300d\u3092\u30aa\u30d5\u306b\u5207\u308a\u66ff\u3048\u307e\u3059\u3002.<\/li>\n\n\n\n<li>Firefox: \u300c\u30aa\u30d5\u300d\u306b\u8a2d\u5b9a\u3059\u308b\u304b\u3001\u5165\u529b\u3057\u307e\u3059 <code>about:config<\/code> \u305d\u3057\u3066\u8a2d\u5b9a\u3057\u307e\u3059 <code>network.trr.mode = 5<\/code>.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"dns-over-tls-dot-vs-doh\">DNS over TLS (DoT) \u5bfe DoH<\/h3>\n\n\n<p>DoT\u306f\u3001\u30dd\u30fc\u30c8443\u3067HTTPS\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\u3068\u6df7\u5728\u3055\u305b\u308b\u4ee3\u308f\u308a\u306b\u3001\u5c02\u7528\u30dd\u30fc\u30c8\uff08853\uff09\u3067DNS\u3092\u6697\u53f7\u5316\u3059\u308b\u4ee3\u66ff\u624b\u6bb5\u3067\u3059\u3002DoT\u306f\u4f01\u696d\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u3067\u8b58\u5225\u304a\u3088\u3073\u30d6\u30ed\u30c3\u30af\/\u7ba1\u7406\u304c\u5bb9\u6613\u3067\u3059\u3002DoH\u306f\u901a\u5e38\u306eWeb\u30c8\u30e9\u30d5\u30a3\u30c3\u30af\u3068\u6df7\u5728\u3057\u3001\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u304c\u96e3\u3057\u304f\u306a\u308a\u307e\u3059\u3002\u5bb6\u5ead\u30e6\u30fc\u30b6\u30fc\u306b\u306f\u3069\u3061\u3089\u3082\u6a5f\u80fd\u3057\u307e\u3059\u3002\u53ef\u8996\u6027\u304c\u5fc5\u8981\u306a\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u7ba1\u7406\u8005\u306b\u306f\u3001\u4e00\u822c\u7684\u306bDoT\u304c\u63a8\u5968\u3055\u308c\u307e\u3059\u3002.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"local-cache\">\u30b9\u30c6\u30c3\u30d78: \u30ed\u30fc\u30ab\u30ebDNS\u30ad\u30e3\u30c3\u30b7\u30e5\u30b5\u30fc\u30d0\u30fc\u3092\u5b9f\u884c\u3059\u308b<\/h2>\n\n\n<p>\u30d1\u30ef\u30fc\u30e6\u30fc\u30b6\u30fc\u3068\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u7ba1\u7406\u8005\u306b\u3068\u3063\u3066\u3001\u30ed\u30fc\u30ab\u30eb\u30ad\u30e3\u30c3\u30b7\u30e5DNS\u30ea\u30be\u30eb\u30d0\u3092\u5b9f\u884c\u3059\u308b\u3053\u3068\u3067\u3001\u7e70\u308a\u8fd4\u3057\u306e\u30af\u30a8\u30ea\u306b\u5bfe\u3059\u308b\u5f80\u5fa9\u3092\u5b8c\u5168\u306b\u6392\u9664\u3067\u304d\u307e\u3059\u3002\u6bce\u56de\u30ea\u30e2\u30fc\u30c8DNS\u30b5\u30fc\u30d0\u30fc\u306b\u30a2\u30af\u30bb\u30b9\u3059\u308b\u4ee3\u308f\u308a\u306b\u3001\u30ed\u30fc\u30ab\u30eb\u30ad\u30e3\u30c3\u30b7\u30e5\u304c\u5373\u5ea7\u306b\u5fdc\u7b54\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"popular-options\">\u4eba\u6c17\u306e\u30aa\u30d7\u30b7\u30e7\u30f3<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u30a2\u30f3\u30d0\u30a6\u30f3\u30c9<\/strong> \u2014 \u691c\u8a3c\u3001\u518d\u5e30\u3001\u30ad\u30e3\u30c3\u30b7\u30e5DNS\u30ea\u30be\u30eb\u30d0\u3002\u5358\u4e00\u306e\u30d1\u30d6\u30ea\u30c3\u30afDNS\u30b5\u30fc\u30d0\u30fc\u304c\u3059\u3079\u3066\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u6301\u3064\u3053\u3068\u3092\u9632\u304e\u307e\u3059\u3002\u4e0a\u6d41\u306e\u6697\u53f7\u5316\u306bDoT\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>dnsmasq<\/strong> \u2014 \u8efd\u91cf\u306aDNS\u30d5\u30a9\u30ef\u30fc\u30c0\u30fc\u304a\u3088\u3073DHCP\u30b5\u30fc\u30d0\u30fc\u3002Linux\u30eb\u30fc\u30bf\u30fc\u3067\u306e\u8a2d\u5b9a\u304c\u7c21\u5358\u3067\u3059\u3002.<\/li>\n\n\n\n<li><strong>Pi-hole<\/strong> \u2014 \u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u5168\u4f53\u306e\u5e83\u544a\u30d6\u30ed\u30c3\u30ab\u30fc\u3067\u3042\u308a\u3001DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u3068\u3057\u3066\u3082\u6a5f\u80fd\u3057\u307e\u3059\u3002DNS\u30ec\u30d9\u30eb\u3067\u5e83\u544a\u3084\u30c8\u30e9\u30c3\u30ab\u30fc\u3092\u30d6\u30ed\u30c3\u30af\u3057\u3001\u3059\u3079\u3066\u306e\u30c7\u30d0\u30a4\u30b9\u306e\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u524a\u6e1b\u3057\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"quick-setup-unbound-on-linux\">\u30af\u30a4\u30c3\u30af\u30bb\u30c3\u30c8\u30a2\u30c3\u30d7: Linux\u3067\u306eUnbound<\/h3>\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp># Unbound\u3092\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb<br>sudo apt install unbound<br><br># \u57fa\u672c\u8a2d\u5b9a: \/etc\/unbound\/unbound.conf<br>\u30b5\u30fc\u30d0\u30fc:<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30a4\u30f3\u30bf\u30fc\u30d5\u30a7\u30fc\u30b9: 127.0.0.1<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30dd\u30fc\u30c8: 53<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30a2\u30af\u30bb\u30b9\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb: 127.0.0.0\/8 \u8a31\u53ef<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30ad\u30e3\u30c3\u30b7\u30e5\u6700\u5c0fTTL: 300<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30ad\u30e3\u30c3\u30b7\u30e5\u6700\u5927TTL: 86400<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1: \u306f\u3044<br><br># Cloudflare\u306bTLS\u3067\u30d5\u30a9\u30ef\u30fc\u30c9<br>\u30d5\u30a9\u30ef\u30fc\u30c9\u30be\u30fc\u30f3:<br>&nbsp;&nbsp;&nbsp;&nbsp;\u540d\u524d: \u201c.\u201d<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30d5\u30a9\u30ef\u30fc\u30c9TLS\u4e0a\u6d41: \u306f\u3044<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30d5\u30a9\u30ef\u30fc\u30c9\u30a2\u30c9\u30ec\u30b9: 1.1.1.1@853<br>&nbsp;&nbsp;&nbsp;&nbsp;\u30d5\u30a9\u30ef\u30fc\u30c9\u30a2\u30c9\u30ec\u30b9: 1.0.0.1@853<br><br># \u958b\u59cb\u3068\u6709\u52b9\u5316<br>sudo systemctl enable unbound<br>sudo systemctl start unbound<br><br># \u30b7\u30b9\u30c6\u30e0\u3092\u30ed\u30fc\u30ab\u30eb\u30ea\u30be\u30eb\u30d0\u3092\u4f7f\u7528\u3059\u308b\u3088\u3046\u306b\u8a2d\u5b9a<br># \/etc\/resolv.conf\u3092\u7de8\u96c6:<br>nameserver 127.0.0.1<\/samp><\/p>\n<\/blockquote>\n\n\n\n<p>AI CRM <code>\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1: \u306f\u3044<\/code>, Unbound\u306f\u983b\u7e41\u306b\u30a2\u30af\u30bb\u30b9\u3055\u308c\u308b\u30ec\u30b3\u30fc\u30c9\u3092\u671f\u9650\u5207\u308c\u524d\u306b\u66f4\u65b0\u3059\u308b\u305f\u3081\u3001\u30b3\u30fc\u30eb\u30c9\u30ad\u30e3\u30c3\u30b7\u30e5\u30df\u30b9\u3092\u307b\u3068\u3093\u3069\u7d4c\u9a13\u3057\u307e\u305b\u3093\u3002.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"browser\">\u30b9\u30c6\u30c3\u30d79: \u30d6\u30e9\u30a6\u30b6\u56fa\u6709\u306eDNS\u554f\u984c\u3092\u4fee\u6b63\u3059\u308b<\/h2>\n\n\n<p>\u30d6\u30e9\u30a6\u30b6\u306b\u306f\u3001OS\u8a2d\u5b9a\u3092\u4e0a\u66f8\u304d\u3067\u304d\u308b\u72ec\u81ea\u306eDNS\u52d5\u4f5c\u304c\u3042\u308a\u307e\u3059:<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"chrome-edge\">Chrome \/ Edge<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li>\u7d44\u307f\u8fbc\u307f\u306e\u300c\u30bb\u30ad\u30e5\u30a2DNS\u300d\uff08DoH\uff09\u306fOS\u30ec\u30d9\u30eb\u306eDNS\u3092\u4e0a\u66f8\u304d\u3067\u304d\u307e\u3059\u3002\u78ba\u8a8d: \u8a2d\u5b9a \u2192 \u30d7\u30e9\u30a4\u30d0\u30b7\u30fc \u2192 \u300c\u30bb\u30ad\u30e5\u30a2DNS\u3092\u4f7f\u7528\u3059\u308b\u300d\u3002\u201c<\/li>\n\n\n\n<li>Chrome\u306f\u72ec\u81ea\u306eDNS\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u4fdd\u6301\u3057\u307e\u3059\u3002\u30af\u30ea\u30a2\u3059\u308b\u306b\u306f <code>chrome:\/\/net-internals\/#dns<\/code> \u2192 \u300c\u30db\u30b9\u30c8\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u30af\u30ea\u30a2\u300d\u3002\u201c<\/li>\n\n\n\n<li>\u30bd\u30b1\u30c3\u30c8\u30d7\u30fc\u30eb\u3082\u30af\u30ea\u30a2: <code>chrome:\/\/net-internals\/#sockets<\/code> \u2192 \u300c\u30bd\u30b1\u30c3\u30c8\u30d7\u30fc\u30eb\u3092\u30d5\u30e9\u30c3\u30b7\u30e5\u300d\u3002\u201c<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"firefox\">Firefox<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li>Firefox\u306b\u306f\u3001\u7c73\u56fd\u30e6\u30fc\u30b6\u30fc\u5411\u3051\u306bCloudflare DoH\u3092\u30c7\u30d5\u30a9\u30eb\u30c8\u3068\u3059\u308b\u72ec\u81ea\u306e\u4fe1\u983c\u3067\u304d\u308b\u518d\u5e30\u30ea\u30be\u30eb\u30d0\uff08TRR\uff09\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u308c\u306b\u3088\u308a\u3001OS\u306eDNS\u8a2d\u5b9a\u304c\u5b8c\u5168\u306b\u30d0\u30a4\u30d1\u30b9\u3055\u308c\u307e\u3059\u3002.<\/li>\n\n\n\n<li>\u30b9\u30c6\u30fc\u30bf\u30b9\u3092\u78ba\u8a8d: <code>about:networking#dns<\/code> \u30ad\u30e3\u30c3\u30b7\u30e5\u3055\u308c\u305fDNS\u30a8\u30f3\u30c8\u30ea\u3068\u30a2\u30af\u30c6\u30a3\u30d6\u306a\u30ea\u30be\u30eb\u30d0\u3092\u78ba\u8a8d\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li>TRR\u3092\u7121\u52b9\u306b\u3059\u308b\u306b\u306f: \u8a2d\u5b9a \u2192 \u30d7\u30e9\u30a4\u30d0\u30b7\u30fc\u3068\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3 \u2192 DNS over HTTPS \u2192 \u30aa\u30d5\u3002.<\/li>\n\n\n\n<li>\u8a2d\u5b9a\u3067\u5f37\u5236\u7121\u52b9\u5316: <code>about:config<\/code> \u2192 \u8a2d\u5b9a <code>network.trr.mode<\/code> \u3078 <code>5<\/code>.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"all-browsers\">\u3059\u3079\u3066\u306e\u30d6\u30e9\u30a6\u30b6<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li>\u62e1\u5f35\u6a5f\u80fd\uff08\u5e83\u544a\u30d6\u30ed\u30c3\u30ab\u30fc\u3001\u30d7\u30e9\u30a4\u30d0\u30b7\u30fc\u30c4\u30fc\u30eb\uff09\u306fDNS\u3092\u508d\u53d7\u3057\u3066\u30ea\u30c0\u30a4\u30ec\u30af\u30c8\u3067\u304d\u307e\u3059\u3002\u62e1\u5f35\u6a5f\u80fd\u3092\u7121\u52b9\u306b\u3057\u3066\u30b7\u30fc\u30af\u30ec\u30c3\u30c8\/\u30d7\u30e9\u30a4\u30d9\u30fc\u30c8\u30e2\u30fc\u30c9\u3067\u30c6\u30b9\u30c8\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li>DNS\u304c\u6a5f\u80fd\u3059\u308b\u5834\u5408 <code>\u6398\u308b<\/code> \u307e\u305f\u306f <code>nslookup<\/code> \u3057\u304b\u3057\u30d6\u30e9\u30a6\u30b6\u304c\u9045\u3044\u5834\u5408\u3001\u554f\u984c\u306f\u30d6\u30e9\u30a6\u30b6\u30ec\u30d9\u30eb\u3067\u3042\u308a\u3001\u30b7\u30b9\u30c6\u30e0DNS\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/li>\n<\/ul>\n\n\n<h2 class=\"wp-block-heading\" id=\"optimize-records\">\u30b9\u30c6\u30c3\u30d710: DNS\u30ec\u30b3\u30fc\u30c9\u3092\u6700\u9069\u5316\u3059\u308b\uff08\u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u6240\u6709\u8005\u5411\u3051\uff09<\/h2>\n\n\n<p>\u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u3092\u7ba1\u7406\u3057\u3066\u3044\u3066\u3001\u8a2a\u554f\u8005\u306b\u3068\u3063\u3066DNS\u304c\u9045\u3044\u5834\u5408\u3001\u3053\u308c\u3089\u306e\u6700\u9069\u5316\u304c\u9069\u7528\u3055\u308c\u307e\u3059:<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"reduce-and-clean-up-records\">\u30ec\u30b3\u30fc\u30c9\u306e\u524a\u6e1b\u3068\u30af\u30ea\u30fc\u30f3\u30a2\u30c3\u30d7<\/h3>\n\n\n<p>\u672a\u4f7f\u7528\u306eA\u3001CNAME\u3001TXT\u3001\u304a\u3088\u3073MX\u30ec\u30b3\u30fc\u30c9\u3092\u524a\u9664\u3057\u307e\u3059\u3002\u4f59\u5206\u306a\u30ec\u30b3\u30fc\u30c9\u306f\u89e3\u6c7a\u6642\u306b\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002DNS\u30be\u30fc\u30f3\u30d5\u30a1\u30a4\u30eb\u3092\u56db\u534a\u671f\u3054\u3068\u306b\u76e3\u67fb\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"eliminate-cname-chaining\">CNAME\u30c1\u30a7\u30fc\u30f3\u306e\u6392\u9664<\/h3>\n\n\n<p>CNAME \u2192 CNAME \u2192 A\u30ec\u30b3\u30fc\u30c9\u306e\u4ee3\u308f\u308a\u306b\u3001\u30c9\u30e1\u30a4\u30f3\u3092\u6700\u7d42IP\u306b\u76f4\u63a5A\u30ec\u30b3\u30fc\u30c9\u3067\u30dd\u30a4\u30f3\u30c8\u3057\u307e\u3059\u3002\u591a\u304f\u306eDNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306f <strong>CNAME\u30d5\u30e9\u30c3\u30c6\u30f3<\/strong> \uff08ALIAS\u30ec\u30b3\u30fc\u30c9\u3068\u3082\u547c\u3070\u308c\u308b\uff09\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u3066\u304a\u308a\u3001\u30b5\u30fc\u30d0\u30fc\u5074\u3067\u30c1\u30a7\u30fc\u30f3\u3092\u89e3\u6c7a\u3057\u3001\u5358\u4e00\u306e\u30af\u30a8\u30ea\u3067IP\u3092\u8fd4\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"set-appropriate-ttl-values\">\u9069\u5207\u306aTTL\u5024\u306e\u8a2d\u5b9a<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5b89\u5b9a\u3057\u305f\u30ec\u30b3\u30fc\u30c9:<\/strong> \u30ad\u30e3\u30c3\u30b7\u30e5\u306e\u5229\u70b9\u3092\u6700\u5927\u5316\u3059\u308b\u305f\u3081\u306b\u9ad8\u3044TTL\uff083600\u201386400\u79d2\uff09\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u983b\u7e41\u306b\u5909\u66f4\u3055\u308c\u308b\u30ec\u30b3\u30fc\u30c9:<\/strong> 300\u2013600\u79d2\uff085\u201310\u5206\uff09\u306eTTL\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li>\u30ec\u30b3\u30fc\u30c9\u304c\u672c\u5f53\u306b\u5909\u66f4\u3055\u308c\u306a\u3044\u5834\u5408\u3092\u9664\u304d\u3001TTL\u309286400\uff0824\u6642\u9593\uff09\u306b\u8a2d\u5b9a\u3057\u306a\u3044\u3067\u304f\u3060\u3055\u3044\u3002\u3053\u308c\u306f\u66f4\u65b0\u306e\u4f1d\u64ad\u3092\u9045\u3089\u305b\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"dnssec-considerations\">DNSSEC\u306e\u8003\u616e\u4e8b\u9805<\/h3>\n\n\n<p>DNSSEC\u306f\u3001\u30ad\u30e3\u30c3\u30b7\u30e5\u30dd\u30a4\u30ba\u30cb\u30f3\u30b0\u3084\u306a\u308a\u3059\u307e\u3057\u3092\u9632\u3050\u305f\u3081\u306bDNS\u5fdc\u7b54\u306b\u6697\u53f7\u7f72\u540d\u691c\u8a3c\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u5404\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u306b\u51e6\u7406\u6642\u9593\u304c\u8ffd\u52a0\u3055\u308c\u307e\u3059\u3002\u30c8\u30ec\u30fc\u30c9\u30aa\u30d5\u306f\u3001\u308f\u305a\u304b\u306a\u9045\u5ef6\u5897\u52a0\u3067\u5927\u5e45\u306b\u5411\u4e0a\u3057\u305f\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u3067\u3059\u3002\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u304c\u512a\u5148\u3055\u308c\u308b\u5834\u5408\u306fDNSSEC\u3092\u6709\u52b9\u306b\u3057\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u7279\u306b\u9045\u3044\u6a29\u5a01\u30cd\u30fc\u30e0\u30b5\u30fc\u30d0\u30fc\u3067\u306f\u89e3\u6c7a\u6642\u9593\u304c\u308f\u305a\u304b\u306b\u5897\u52a0\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"use-a-premium-dns-provider-cdn\">\u30d7\u30ec\u30df\u30a2\u30e0DNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\/CDN\u3092\u4f7f\u7528<\/h3>\n\n\n<p>\u30c9\u30e1\u30a4\u30f3\u767b\u9332\u8005\u304b\u3089\u306e\u7121\u6599DNS\u306f\u901a\u5e38\u9045\u3044\u3067\u3059\u3002\u30d7\u30ec\u30df\u30a2\u30e0DNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\uff08Cloudflare\u3001AWS Route 53\u3001Dyn\u3001DNS Made Easy\uff09\u306f\u3001\u4f4e\u9045\u5ef6\u5fdc\u7b54\u306e\u305f\u3081\u306b\u8a2d\u8a08\u3055\u308c\u305f\u5927\u898f\u6a21\u3067\u30b0\u30ed\u30fc\u30d0\u30eb\u306b\u5206\u6563\u3055\u308c\u305f\u30a8\u30cb\u30fc\u30ad\u30e3\u30b9\u30c8\u30a4\u30f3\u30d5\u30e9\u30b9\u30c8\u30e9\u30af\u30c1\u30e3\u3092\u6301\u3063\u3066\u3044\u307e\u3059\u3002Cloudflare\u3084Akamai\u306e\u3088\u3046\u306aCDN\u306f\u3001\u72ec\u81ea\u306eDNS\u30a4\u30f3\u30d5\u30e9\u30b9\u30c8\u30e9\u30af\u30c1\u30e3\u3092\u6301\u3061\u3001\u30b0\u30ed\u30fc\u30d0\u30eb\u306b\u5206\u6563\u3055\u308c\u305f\u30d7\u30ec\u30bc\u30f3\u30b9\u30dd\u30a4\u30f3\u30c8\u3092\u6301\u3061\u3001\u4e16\u754c\u4e2d\u306e\u30e6\u30fc\u30b6\u30fc\u306e\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u6642\u9593\u3092\u77ed\u7e2e\u3057\u307e\u3059\u3002.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"reduce-domains\">\u30b9\u30c6\u30c3\u30d711: \u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u30c9\u30e1\u30a4\u30f3\u3092\u6e1b\u3089\u3059\uff08\u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u6240\u6709\u8005\u5411\u3051\uff09<\/h2>\n\n\n<p>\u3042\u306a\u305f\u306e\u30a6\u30a7\u30d6\u30b5\u30a4\u30c8\u304c\u30ed\u30fc\u30c9\u3059\u308b\u5404\u30e6\u30cb\u30fc\u30af\u306a\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u30c9\u30e1\u30a4\u30f3\u306f\u3001\u5225\u3005\u306eDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u5fc5\u8981\u3068\u3057\u307e\u3059\u3002\u3053\u308c\u3089\u306f\u3059\u3050\u306b\u7d2f\u7a4d\u3057\u307e\u3059\u20147\u3064\u306e\u5916\u90e8\u30c9\u30e1\u30a4\u30f3\u304b\u3089\u30ea\u30bd\u30fc\u30b9\u3092\u30ed\u30fc\u30c9\u3059\u308b\u30b5\u30a4\u30c8\u306f\u3001DNS\u6642\u9593\u3060\u3051\u30671\u79d2\u4ee5\u4e0a\u3092\u7d2f\u7a4d\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"how-to-reduce\">\u6e1b\u5c11\u65b9\u6cd5<\/h3>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5916\u90e8\u30ea\u30bd\u30fc\u30b9\u306e\u76e3\u67fb:<\/strong> \u30d6\u30e9\u30a6\u30b6\u306eDevTools\uff08\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30bf\u30d6\uff09\u307e\u305f\u306fWebPageTest\u3092\u4f7f\u7528\u3057\u3066\u3001\u30b5\u30a4\u30c8\u304c\u547c\u3073\u51fa\u3059\u3059\u3079\u3066\u306e\u30e6\u30cb\u30fc\u30af\u306a\u30c9\u30e1\u30a4\u30f3\u3092\u7279\u5b9a\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u53ef\u80fd\u306a\u9650\u308a\u81ea\u793e\u30db\u30b9\u30c6\u30a3\u30f3\u30b0:<\/strong> \u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u306e\u30d5\u30a9\u30f3\u30c8\u3001\u30b9\u30af\u30ea\u30d7\u30c8\u3001\u30a2\u30bb\u30c3\u30c8\u3092\u30c0\u30a6\u30f3\u30ed\u30fc\u30c9\u3057\u3001\u30aa\u30ea\u30b8\u30f3\u30b5\u30fc\u30d0\u30fc\u307e\u305f\u306fCDN\u306b\u30db\u30b9\u30c8\u3057\u307e\u3059\u3002\u3053\u308c\u306b\u3088\u308a\u3001\u3053\u308c\u3089\u306eDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u304c\u5b8c\u5168\u306b\u6392\u9664\u3055\u308c\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>CDN\u30c9\u30e1\u30a4\u30f3\u306e\u7d71\u5408:<\/strong> \u8907\u6570\u306e\u5916\u90e8\u30db\u30b9\u30c8\u306e\u4ee3\u308f\u308a\u306b\u5358\u4e00\u306eCDN\u30b5\u30d6\u30c9\u30e1\u30a4\u30f3\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002.<\/li>\n\n\n\n<li><strong>\u672a\u4f7f\u7528\u306e\u30d7\u30e9\u30b0\u30a4\u30f3\u3068\u30c8\u30e9\u30c3\u30ab\u30fc\u3092\u524a\u9664:<\/strong> \u5916\u90e8JavaScript\u3092\u30ed\u30fc\u30c9\u3059\u308b\u5404\u30d7\u30e9\u30b0\u30a4\u30f3\u306f\u3001\u5c11\u306a\u304f\u3068\u30821\u3064\u306eDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3068\u30b9\u30af\u30ea\u30d7\u30c8\u81ea\u4f53\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002.<\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"defer-noncritical-javascript\">\u975e\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u306aJavaScript\u306e\u9045\u5ef6<\/h3>\n\n\n<p>\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u306eJavaScript\u306f\u3057\u3070\u3057\u3070\u8ffd\u52a0\u306e\u5916\u90e8\u30c9\u30e1\u30a4\u30f3\u3092\u30ed\u30fc\u30c9\u3057\u307e\u3059\u3002\u975e\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u306aJS\u3092\u9045\u5ef6\u3055\u305b\u308b\u3053\u3068\u3067\u3001\u3053\u308c\u3089\u306eDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u30e1\u30a4\u30f3\u30da\u30fc\u30b8\u306e\u30ec\u30f3\u30c0\u30ea\u30f3\u30b0\u5f8c\u307e\u3067\u9045\u3089\u305b\u307e\u3059:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp>&lt;!&#8211; Defer non-critical third-party scripts &#8211;&gt;<br>&lt;script src=&#8221;https:\/\/analytics.example.com\/tracker.js&#8221; defer&gt;&lt;\/script&gt;<br><br>&lt;!&#8211; Async for scripts that don&#8217;t depend on page load order &#8211;&gt;<br>&lt;script src=&#8221;https:\/\/ads.example.com\/ad.js&#8221; async&gt;&lt;\/script&gt;<\/samp><\/p>\n<\/blockquote>\n\n\n\n<p>\u30bd\u30fc\u30b7\u30e3\u30eb\u30e1\u30c7\u30a3\u30a2\u5206\u6790\u3092\u4f7f\u7528\u3057\u3001 <code>\u30c7\u30a3\u30d5\u30a1\u30fc<\/code> \u307e\u305f\u306f <code>\u975e\u540c\u671f<\/code> \u3053\u308c\u3089\u306e\u30b9\u30af\u30ea\u30d7\u30c8\u304c\u30e1\u30a4\u30f3\u30da\u30fc\u30b8\u306e\u30ec\u30f3\u30c0\u30ea\u30f3\u30b0\u3092\u30d6\u30ed\u30c3\u30af\u3059\u308b\u306e\u3092\u9632\u304e\u306a\u304c\u3089\u3001\u305d\u308c\u3089\u3092\u30ed\u30fc\u30c9\u3057\u307e\u3059\u3002\u3053\u308c\u3089\u306e\u30c9\u30e1\u30a4\u30f3\u306eDNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u306f\u4f9d\u7136\u3068\u3057\u3066\u767a\u751f\u3057\u307e\u3059\u304c\u3001\u30e6\u30fc\u30b6\u30fc\u304c\u30b3\u30f3\u30c6\u30f3\u30c4\u3092\u898b\u308b\u306e\u3092\u59a8\u3052\u307e\u305b\u3093\u3002.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"prefetch\">\u30b9\u30c6\u30c3\u30d712: DNS\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1\u3092\u5b9f\u88c5\u3059\u308b\uff08\u30a6\u30a7\u30d6\u958b\u767a\u8005\u5411\u3051\uff09<\/h2>\n\n\n<p>\u6700\u65b0\u306e\u30d6\u30e9\u30a6\u30b6\u306f <code>DNS\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1<\/code> \u305d\u3057\u3066 <code>\u30d7\u30ec\u30b3\u30cd\u30af\u30c8<\/code> \u30ea\u30bd\u30fc\u30b9\u30d2\u30f3\u30c8\u3092\u30b5\u30dd\u30fc\u30c8\u3057\u3066\u304a\u308a\u3001\u30e6\u30fc\u30b6\u30fc\u304c\u305d\u308c\u3092\u5fc5\u8981\u3068\u3059\u308b\u524d\u306b\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u30c9\u30e1\u30a4\u30f3\u306eDNS\u3092\u89e3\u6c7a\u3057\u307e\u3059:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><samp>&lt;!&#8211; DNS prefetch for non-critical third-party domains &#8211;&gt;<br>&lt;link rel=&#8221;dns-prefetch&#8221; href=&#8221;https:\/\/fonts.googleapis.com&#8221;&gt;<br>&lt;link rel=&#8221;dns-prefetch&#8221; href=&#8221;https:\/\/analytics.example.com&#8221;&gt;<br><br>&lt;!&#8211; Preconnect for critical third-party domains (DNS + TCP + TLS) &#8211;&gt;<br>&lt;link rel=&#8221;preconnect&#8221; href=&#8221;https:\/\/cdn.example.com&#8221;&gt;<br>&lt;link rel=&#8221;preconnect&#8221; href=&#8221;https:\/\/api.example.com&#8221;&gt;<\/samp><\/p>\n<\/blockquote>\n\n\n\n<p>\u7528\u9014 <code>\u30d7\u30ec\u30b3\u30cd\u30af\u30c8<\/code> \u6700\u3082\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u306a\u63a5\u7d9a\u306e\u305f\u3081\u306b\uff08DNS + TCP + TLS\u3092\u51e6\u7406\u3057\u307e\u3059\uff09\u305d\u3057\u3066 <code>DNS\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1<\/code> \u4ed6\u306e\u3059\u3079\u3066\u306e\u305f\u3081\u306b\u3002\u30d7\u30ea\u30b3\u30cd\u30af\u30c8\u306f\u63a5\u7d9a\u3054\u3068\u306b100\u2013500 ms\u3092\u7bc0\u7d04\u3067\u304d\u3001DNS\u30d7\u30ea\u30d5\u30a7\u30c3\u30c1\u306f20\u2013120 ms\u3092\u7bc0\u7d04\u3057\u307e\u3059\u3002\u30d7\u30ea\u30b3\u30cd\u30af\u30c8\u3092\u904e\u5ea6\u306b\u4f7f\u7528\u3057\u306a\u3044\u3067\u304f\u3060\u3055\u3044\u2014\u5404\u63a5\u7d9a\u306f\u30ea\u30bd\u30fc\u30b9\u3092\u6d88\u8cbb\u3059\u308b\u63a5\u7d9a\u3092\u958b\u304d\u307e\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n<h2 class=\"wp-block-heading\" id=\"troubleshooting\">\u30af\u30a4\u30c3\u30af\u30ea\u30d5\u30a1\u30ec\u30f3\u30b9\u306e\u30c8\u30e9\u30d6\u30eb\u30b7\u30e5\u30fc\u30c6\u30a3\u30f3\u30b0\u8868<\/h2>\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><th>\u75c7\u72b6<\/th><th>\u8003\u3048\u3089\u308c\u308b\u539f\u56e0<\/th><th>\u4fee\u6b63<\/th><\/tr><tr><td>\u3059\u3079\u3066\u306e\u30b5\u30a4\u30c8\u304c\u521d\u56de\u8a2a\u554f\u6642\u306b\u9045\u304f\u30ed\u30fc\u30c9\u3055\u308c\u308b<\/td><td>\u9045\u3044ISP DNS\u30ea\u30be\u30eb\u30d0<\/td><td>Cloudflare\uff081.1.1.1\uff09\u307e\u305f\u306fGoogle\uff088.8.8.8\uff09\u306b\u5207\u308a\u66ff\u3048\u307e\u3059\u3002\u307e\u305a\u30eb\u30fc\u30bf\u30fc\u3092\u518d\u8d77\u52d5\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>\u30da\u30fc\u30b8\u304c\u30ed\u30fc\u30c9\u3092\u958b\u59cb\u3059\u308b\u524d\u306b5\u79d2\u306e\u9045\u5ef6<\/td><td>IPv6\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u9045\u5ef6<\/td><td>\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u3067IPv6\u3092\u7121\u52b9\u306b\u3059\u308b\u304b\u3001OS\u3092IPv4\u3092\u512a\u5148\u3059\u308b\u3088\u3046\u306b\u8a2d\u5b9a\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>\u7279\u5b9a\u306e\u30c9\u30e1\u30a4\u30f3\u304c\u89e3\u6c7a\u3057\u306a\u3044<\/td><td>\u53e4\u3044DNS\u30ad\u30e3\u30c3\u30b7\u30e5<\/td><td>OS\u3068\u30d6\u30e9\u30a6\u30b6\u3067DNS\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u30d5\u30e9\u30c3\u30b7\u30e5\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>\u30bf\u30fc\u30df\u30ca\u30eb\u3067DNS\u304c\u6a5f\u80fd\u3059\u308b\u304c\u30d6\u30e9\u30a6\u30b6\u304c\u9045\u3044<\/td><td>\u30d6\u30e9\u30a6\u30b6\u306eDoH\u30aa\u30fc\u30d0\u30fc\u30e9\u30a4\u30c9\u307e\u305f\u306f\u62e1\u5f35\u6a5f\u80fd\u306e\u5e72\u6e09<\/td><td>Chrome\/Firefox\u306e\u30bb\u30ad\u30e5\u30a2DNS\u8a2d\u5b9a\u3092\u78ba\u8a8d\u3057\u307e\u3059\u3002\u62e1\u5f35\u6a5f\u80fd\u3092\u7121\u52b9\u306b\u3057\u3066\u30b7\u30fc\u30af\u30ec\u30c3\u30c8\u30e2\u30fc\u30c9\u3067\u30c6\u30b9\u30c8\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>VPN\u63a5\u7d9a\u6642\u306e\u307fDNS\u304c\u9045\u3044<\/td><td>VPN DNS\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0<\/td><td>VPN\u8a2d\u5b9a\u3067\u30ab\u30b9\u30bf\u30e0DNS\u3092\u69cb\u6210\u3059\u308b\u304b\u3001dnsleaktest.com\u3067DNS\u30ea\u30fc\u30af\u3092\u78ba\u8a8d\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>\u30a6\u30a4\u30eb\u30b9\u5bfe\u7b56\u5b9f\u884c\u6642\u306b\u65ad\u7d9a\u7684\u306bDNS\u304c\u9045\u3044<\/td><td>\u30a6\u30a4\u30eb\u30b9\u5bfe\u7b56\u306eDNS\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0<\/td><td>\u4e00\u6642\u7684\u306b\u30a6\u30a7\u30d6\u4fdd\u8b77\u3092\u7121\u52b9\u306b\u3057\u307e\u3059\u3002\u3088\u308a\u901f\u3044\u5834\u5408\u306fDNS\u30b5\u30fc\u30d0\u30fc\u306e\u4f8b\u5916\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>dig +trace\u304c1\u30db\u30c3\u30d7\u3067&gt;200 ms\u3092\u793a\u3059<\/td><td>\u9045\u3044\u6a29\u5a01\u30cd\u30fc\u30e0\u30b5\u30fc\u30d0\u30fc<\/td><td>CDN\u30a2\u30fc\u30ad\u30c6\u30af\u30c1\u30e3\u3092\u6301\u3064DNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u306b\u5207\u308a\u66ff\u3048\u308b\u304b\u3001CNAME\u30d5\u30e9\u30c3\u30c6\u30f3\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>PageSpeed \/ WebPageTest\u3067\u9ad8\u3044DNS\u6642\u9593<\/td><td>\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u30c9\u30e1\u30a4\u30f3\u304c\u591a\u3059\u304e\u308b<\/td><td>dns-prefetch \/ preconnect\u30d2\u30f3\u30c8\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u5916\u90e8\u30c9\u30e1\u30a4\u30f3\u3092\u524a\u6e1b\u3057\u307e\u3059\u3002\u975e\u30af\u30ea\u30c6\u30a3\u30ab\u30eb\u306aJS\u3092\u9045\u5ef6\u3055\u305b\u307e\u3059\u3002.<\/td><\/tr><tr><td>DNS\u306f\u6a5f\u80fd\u3059\u308b\u304c\u65ad\u7d9a\u7684\u306b\u9045\u3044<\/td><td>\u904e\u8ca0\u8377\u306e\u30cd\u30fc\u30e0\u30b5\u30fc\u30d0\u30fc\u307e\u305f\u306f\u30b4\u30fc\u30b9\u30c8\u30a2\u30c0\u30d7\u30bf\u30fc<\/td><td>GRC DNS Benchmark\u3067\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u3057\u307e\u3059\u3002\u30d5\u30a1\u30f3\u30c8\u30e0\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc\u3092\u524a\u9664\u3057\u307e\u3059\u3002\u30bb\u30ab\u30f3\u30c0\u30eaDNS\u3092\u691c\u8a0e\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>\u7279\u5b9a\u306e\u5730\u57df\u304b\u3089\u306e\u307fDNS\u304c\u9045\u3044<\/td><td>\u5730\u7406\u7684\u8ddd\u96e2<\/td><td>\u30b0\u30ed\u30fc\u30d0\u30eb\u30a8\u30cb\u30fc\u30ad\u30e3\u30b9\u30c8\u3092\u6301\u3064DNS\u30d7\u30ed\u30d0\u30a4\u30c0\u30fc\u3092\u4f7f\u7528\u3057\u307e\u3059\uff08Cloudflare\u3001Route 53\uff09\u3002.<\/td><\/tr><tr><td>DoH\u30aa\u30f3\u3067\u30ed\u30fc\u30ab\u30eb\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30c9\u30e1\u30a4\u30f3\u304c\u89e3\u6c7a\u3057\u306a\u3044<\/td><td>DoH\u304c\u30ed\u30fc\u30ab\u30ebDNS\u3092\u30d0\u30a4\u30d1\u30b9<\/td><td>\u30d6\u30e9\u30a6\u30b6\u3067DoH\u3092\u7121\u52b9\u306b\u3059\u308b\u304b\u3001\u30b9\u30d7\u30ea\u30c3\u30c8DNS\u3092\u69cb\u6210\u3057\u307e\u3059\u3002\u4f01\u696d\u5411\u3051\u306b\u306fDoT\u3092\u4f7f\u7528\u3057\u307e\u3059\u3002.<\/td><\/tr><tr><td>\u6700\u8fd1\u306e\u30bd\u30d5\u30c8\u30a6\u30a7\u30a2\u30a4\u30f3\u30b9\u30c8\u30fc\u30eb\u5f8c\u306b\u30da\u30fc\u30b8\u304c\u9045\u3044<\/td><td>\u65b0\u3057\u3044VPN\/VM\u304c\u30b4\u30fc\u30b9\u30c8\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u30a2\u30c0\u30d7\u30bf\u30fc\u3092\u8ffd\u52a0<\/td><td>\u30c7\u30d0\u30a4\u30b9\u30de\u30cd\u30fc\u30b8\u30e3\u30fc\u3067\u30d5\u30a1\u30f3\u30c8\u30e0\u30a2\u30c0\u30d7\u30bf\u30fc\u3092\u78ba\u8a8d\u3057\u307e\u3059\u3002\u53e4\u3044DNS\u69cb\u6210\u3092\u524a\u9664\u3057\u307e\u3059\u3002.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p><\/p>","protected":false},"excerpt":{"rendered":"<p>\u9045\u3044DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u306f\u3001\u30d6\u30e9\u30a6\u30b6\u304c\u30a6\u30a7\u30d6\u30da\u30fc\u30b8\u306e\u8aad\u307f\u8fbc\u307f\u3092\u958b\u59cb\u3059\u308b\u524d\u306b\u4e0d\u8981\u306a\u9045\u5ef6\u3092\u8ffd\u52a0\u3057\u307e\u3059\u3002\u901a\u5e38\u306eDNS\u89e3\u6c7a\u306b\u306f20\u301c120\u30df\u30ea\u79d2\u304b\u304b\u308a\u307e\u3059\u304c\u3001\u8aa4\u3063\u305f\u8a2d\u5b9a\u3084\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u4f4e\u3044DNS\u306f\u305d\u308c\u3092\u5927\u5e45\u306b\u9045\u3089\u305b\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u2026 <a class=\"more-link\" href=\"https:\/\/securitybriefing.net\/ja\/%e3%83%86%e3%82%af%e3%83%8e%e3%83%ad%e3%82%b8%e3%83%bc\/%e9%81%85%e3%81%84dns%e3%83%ab%e3%83%83%e3%82%af%e3%82%a2%e3%83%83%e3%83%97%e3%82%92%e4%bf%ae%e6%ad%a3%e3%81%99%e3%82%8b%e6%96%b9%e6%b3%95\/\">\u7d9a\u304d\u3092\u8aad\u3080 <span class=\"screen-reader-text\">\u9045\u3044DNS\u30eb\u30c3\u30af\u30a2\u30c3\u30d7\u3092\u4fee\u6b63\u3059\u308b\u65b9\u6cd5<\/span><\/a><\/p>","protected":false},"author":3,"featured_media":5248,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[30],"tags":[],"class_list":["post-5245","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tech","entry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.8 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How to Fix Slow DNS Lookup: 12-Step Diagnostic &amp; Fix<\/title>\n<meta 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