{"id":1381,"date":"2026-10-25T19:00:00","date_gmt":"2026-10-25T10:00:00","guid":{"rendered":"https:\/\/quantumsea.net\/?p=1381"},"modified":"2026-10-23T06:21:06","modified_gmt":"2026-10-22T21:21:06","slug":"qs-dns-dname-descendant-substitution-20261023","status":"publish","type":"post","link":"https:\/\/quantumsea.net\/?p=1381","title":{"rendered":"DNS\u306eDNAME\u3001\u679d\u306e\u4e0b\u3092\u79fb\u3057\u3066\u3082\u8d77\u70b9\u306e\u540d\u524d\u304c\u5909\u308f\u3089\u306a\u3044\u7406\u7531"},"content":{"rendered":"<p>\u30c9\u30e1\u30a4\u30f3\u540d\u3092\u4e00\u3064\u305a\u3064\u5225\u540d\u3078\u5bfe\u5fdc\u3055\u305b\u308b\u4ee3\u308f\u308a\u306b\u3001\u540d\u524d\u306e\u6728\u306e\u4e00\u90e8\u5206\u3092\u307e\u3068\u3081\u3066\u5225\u306e\u5834\u6240\u3078\u5411\u3051\u305f\u3044\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002DNS\u306eDNAME\u306f\u3001\u305d\u306e\u305f\u3081\u306e\u30ec\u30b3\u30fc\u30c9\u3067\u3059\u3002\u305f\u3060\u3057\u3001\u8a2d\u5b9a\u3057\u305f\u540d\u524d\u81ea\u8eab\u3068\u3001\u305d\u306e\u4e0b\u306b\u3042\u308b\u540d\u524d\u3067\u306f\u6271\u3044\u304c\u9055\u3044\u307e\u3059\u3002\u3053\u306e\u5883\u754c\u3092\u78ba\u304b\u3081\u306a\u3044\u3068\u3001\u300c\u5168\u90e8\u3092\u79fb\u3057\u305f\u3064\u3082\u308a\u306a\u306e\u306b\u3001\u8d77\u70b9\u3060\u3051\u5143\u306e\u307e\u307e\u300d\u3068\u3044\u3046\u72b6\u614b\u3092\u8aad\u307f\u9055\u3048\u307e\u3059\u3002<\/p>\n<section class=\"influvetor-quick-summary\">\n<p><strong>\u7c21\u5358\u306b\u307e\u3068\u3081\u308b\u3068\uff1f<\/strong><\/p>\n<ul>\n<li>CNAME\u304c\u4e00\u3064\u306e\u540d\u524d\u3092\u5225\u540d\u3078\u5411\u3051\u308b\u306e\u306b\u5bfe\u3057\u3001DNAME\u306f\u8a2d\u5b9a\u3057\u305f\u540d\u524d\u306e\u4e0b\u306b\u3042\u308b\u5b50\u5b6b\u540d\u3092\u3001\u5225\u306e\u679d\u306e\u5bfe\u5fdc\u3059\u308b\u540d\u524d\u3078\u5411\u3051\u307e\u3059\u3002\u8a2d\u5b9a\u3057\u305f\u540d\u524d\u81ea\u8eab\u306f\u7f6e\u304d\u63db\u3048\u307e\u305b\u3093\u3002<\/li>\n<li>\u7f6e\u63db\u3059\u308b\u306e\u306f\u540d\u524d\u306e\u672b\u5c3e\u306b\u4e00\u81f4\u3059\u308b\u30e9\u30d9\u30eb\u306e\u307e\u3068\u307e\u308a\u3067\u3059\u3002api.old.example.\u306a\u3089api.new.example.\u3068\u306a\u308a\u3001\u5de6\u5074\u306eapi\u306f\u6b8b\u308a\u307e\u3059\u3002\u4f3c\u305f\u7db4\u308a\u3092\u542b\u3080\u3060\u3051\u306e\u540d\u524d\u306f\u5bfe\u8c61\u306b\u306a\u308a\u307e\u305b\u3093\u3002<\/li>\n<li>\u5fdc\u7b54\u306b\u306fDNAME\u3068\u3001\u554f\u3044\u5408\u308f\u305b\u305f\u540d\u524d\u306b\u5bfe\u5fdc\u3059\u308b\u5408\u6210CNAME\u304c\u73fe\u308c\u307e\u3059\u3002\u8d77\u70b9\u306e\u30ec\u30b3\u30fc\u30c9\u3001\u79fb\u52d5\u5148\u306e\u5b9f\u30c7\u30fc\u30bf\u3001\u30eb\u30fc\u30d7\u3084\u9577\u3055\u5236\u9650\u3092\u5225\u3005\u306b\u78ba\u304b\u3081\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/li>\n<\/ul>\n<\/section>\n<h2>\u300c\u8a2d\u5b9a\u3057\u305f\u5834\u6240\u300d\u3068\u300c\u305d\u306e\u5b50\u5b6b\u300d\u3092\u5206\u3051\u308b<\/h2>\n<p>DNS\u3067\u306f\u3001\u30c9\u30c3\u30c8\u3067\u533a\u5207\u3063\u305f\u540d\u524d\u306e\u4e00\u90e8\u5206\u3092\u30e9\u30d9\u30eb\u3068\u547c\u3073\u307e\u3059\u3002api.old.example.\u306a\u3089api\u3001old\u3001example\u3068\u3044\u3046\u30e9\u30d9\u30eb\u304c\u4e26\u3073\u3001\u672b\u5c3e\u306e\u30c9\u30c3\u30c8\u306f\u6839\u3092\u793a\u3057\u307e\u3059\u3002\u540d\u524d\u306e\u968e\u5c64\u3092\u305f\u3069\u308b\u3068\u304d\u306f\u3001\u53f3\u5074\u306eexample\u304b\u3089old\u3001\u305d\u306e\u4e0b\u306eapi\u3078\u9032\u307f\u307e\u3059\u3002<\/p>\n<p>\u30ec\u30b3\u30fc\u30c9\u304c\u7f6e\u304b\u308c\u308b\u540d\u524d\u3092owner\u3001\u3053\u3053\u3067\u306f<strong>\u8a2d\u5b9a\u5143\u306e\u540d\u524d<\/strong>\u3068\u547c\u3073\u307e\u3059\u3002CNAME\u306f\u3001\u305d\u306e\u8a2d\u5b9a\u5143\u306e\u540d\u524d\u3067\u30c7\u30fc\u30bf\u3092\u63a2\u3057\u305f\u3068\u304d\u306b\u3001\u5225\u306e\u4e00\u3064\u306e\u540d\u524d\u3078\u6848\u5185\u3057\u307e\u3059\u3002\u4e00\u65b9DNAME\u306f\u3001\u8a2d\u5b9a\u5143\u3088\u308a\u4e0b\u306b\u3042\u308b\u5b50\u5b6b\u540d\u3078\u306e\u554f\u3044\u5408\u308f\u305b\u3092\u5bfe\u8c61\u306b\u3057\u307e\u3059\u3002RFC 6672\u306f\u3053\u306e\u9055\u3044\u3092\u3001\u540d\u524d\u306e\u6728\u306e\u4e00\u90e8\u304b\u3089\u5225\u306e\u90e8\u5206\u3078\u306e\u6848\u5185\u3068\u3057\u3066\u8aac\u660e\u3057\u3066\u3044\u307e\u3059\u3002[1\u3001\u00a71]<\/p>\n<p>\u305f\u3068\u3048\u3070\u8a2d\u5b9a\u5143\u3092old.example.\u3001\u8ee2\u9001\u5148\u3092new.example.\u3068\u3059\u308bDNAME\u3092\u8003\u3048\u307e\u3059\u3002\u554f\u3044\u5408\u308f\u305b\u540d\u304capi.old.example.\u306a\u3089\u3001\u672b\u5c3e\u306eold.example.\u3092new.example.\u3078\u7f6e\u304d\u63db\u3048\u3001api.new.example.\u306b\u3064\u3044\u3066\u8abf\u3079\u307e\u3059\u3002img.eu.old.example.\u306a\u3089\u3001\u5de6\u306b\u3042\u308bimg.eu\u3092\u305d\u306e\u307e\u307e\u6b8b\u3057\u3066img.eu.new.example.\u306b\u306a\u308a\u307e\u3059\u3002\u4e0b\u306e\u968e\u5c64\u304c\u4e00\u6bb5\u3060\u3051\u3067\u3042\u308b\u5fc5\u8981\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n<h2>\u6587\u5b57\u5217\u306e\u90e8\u5206\u4e00\u81f4\u3067\u306f\u306a\u304f\u3001\u30e9\u30d9\u30eb\u3054\u3068\u306e\u7f6e\u63db<\/h2>\n<p>RFC 6672 \u00a72.2\u304c\u5b9a\u3081\u308b\u306e\u306f\u3001\u6839\u307e\u3067\u7d9a\u304f\u672b\u5c3e\u5074\u306e\u30e9\u30d9\u30eb\u306e\u4e00\u81f4\u3067\u3059\u3002old\u3068\u3044\u3046\u6587\u5b57\u3092\u63a2\u3057\u3066\u3069\u3053\u3067\u3082new\u306b\u5909\u3048\u308b\u51e6\u7406\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002notold.example.\u306f\u3001\u30e9\u30d9\u30ebnotold\u304cold\u3068\u4e00\u81f4\u3057\u306a\u3044\u305f\u3081\u3001\u5148\u307b\u3069\u306eDNAME\u3067\u306f\u7f6e\u63db\u3055\u308c\u307e\u305b\u3093\u3002api.old.example.invalid.\u3082\u3001\u672b\u5c3e\u304cold.example.\u3067\u306f\u306a\u3044\u306e\u3067\u5bfe\u8c61\u5916\u3067\u3059\u3002<\/p>\n<p>\u53cd\u5bfe\u306b\u3001old.example.\u305d\u306e\u3082\u306e\u306f\u672b\u5c3e\u304c\u4e00\u81f4\u3057\u3066\u3044\u3066\u3082\u3001DNAME\u306e\u5b50\u5b6b\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002A\u30ec\u30b3\u30fc\u30c9\u306a\u3069\u3092\u554f\u3044\u5408\u308f\u305b\u305f\u5834\u5408\u3001\u305d\u306e\u540d\u524d\u3092new.example.\u3078\u7f6e\u304d\u63db\u3048\u308b\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u3002DNAME\u3068\u3044\u3046\u7a2e\u985e\u305d\u306e\u3082\u306e\u3092\u554f\u3044\u5408\u308f\u305b\u308c\u3070\u3001old.example.\u306b\u3042\u308bDNAME\u30ec\u30b3\u30fc\u30c9\u3092\u53d6\u5f97\u3067\u304d\u307e\u3059\u304c\u3001\u3053\u308c\u3082\u8a2d\u5b9a\u5143\u306e\u540d\u524d\u3092\u5225\u540d\u3078\u5909\u3048\u308b\u3053\u3068\u3068\u306f\u533a\u5225\u3057\u307e\u3059\u3002[1\u3001\u00a72.3]<\/p>\n<figure><img decoding=\"async\" src=\"https:\/\/quantumsea.net\/wp-content\/uploads\/2026\/10\/qs-dns-dname-descendant-substitution-20261023-figure-deceaccfe6e3.png\" alt=\"old.example.\u304b\u3089new.example.\u3078\u306eDNAME\u3002api.old.example.\u306fapi.new.example.\u3078\u3001img.eu.old.example.\u306fimg.eu.new.example.\u3078\u7f6e\u63db\u3002old.example.\u81ea\u8eab\u3068notold.example.\u306f\u7f6e\u63db\u3057\u306a\u3044\u3002\" style=\"width:100%;max-width:100%;height:auto\"><figcaption>\u30e9\u30d9\u30eb\u5358\u4f4d\u306e\u7f6e\u63db\u3092\u8aac\u660e\u3059\u308b\u72ec\u81ea\u4f8b\u3002\u540d\u524d\u89e3\u6c7a\u3084DNS\u8a2d\u5b9a\u5909\u66f4\u3092\u5b9f\u884c\u3057\u305f\u7d50\u679c\u3067\u306f\u306a\u3044\u3002<\/figcaption><\/figure>\n<p>\u3053\u306e\u6bd4\u8f03\u306f\u3001\u30c9\u30c3\u30c8\u3067\u5206\u3051\u305f\u30e9\u30d9\u30eb\u5217\u3067\u72ec\u81ea\u306b\u8a08\u7b97\u3057\u307e\u3057\u305f\u3002\u5b50\u5b6b\u306e\u4e8c\u4f8b\u3001\u8a2d\u5b9a\u5143\u3068\u540c\u3058\u540d\u524d\u3001\u4f3c\u305f\u7db4\u308a\u306e\u540d\u524d\u3001\u672b\u5c3e\u304c\u9055\u3046\u540d\u524d\u3092\u5206\u3051\u3066\u7167\u5408\u3057\u3066\u3044\u307e\u3059\u3002\u5b9f\u88c5\u306f\u8aac\u660e\u7528\u306e\u9650\u3089\u308c\u305fASCII\u540d\u3092\u6271\u3046\u3082\u306e\u3067\u3001DNS\u30d1\u30b1\u30c3\u30c8\u306e\u89e3\u6790\u3001\u56fd\u969b\u5316\u30c9\u30e1\u30a4\u30f3\u540d\u306e\u51e6\u7406\u3001\u554f\u3044\u5408\u308f\u305b\u5148\u306e\u63a2\u7d22\u3092\u518d\u73fe\u3057\u305f\u30ea\u30be\u30eb\u30d0\u30fc\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n<h2>\u5fdc\u7b54\u306bCNAME\u304c\u73fe\u308c\u3066\u3082\u3001\u4e00\u4ef6\u305a\u3064\u767b\u9332\u3057\u305f\u3068\u306f\u9650\u3089\u306a\u3044<\/h2>\n<p>DNAME\u306e\u7f6e\u63db\u3092\u884c\u3046\u30b5\u30fc\u30d0\u30fc\u306f\u3001\u5fdc\u7b54\u306eAnswer\u6b04\u3078\u3001\u305d\u306e\u6839\u62e0\u3068\u306a\u308bDNAME\u3092\u5165\u308c\u307e\u3059\u3002\u3055\u3089\u306b\u3001\u305d\u306e\u554f\u3044\u5408\u308f\u305b\u540d\u304b\u3089\u7f6e\u63db\u5f8c\u306e\u540d\u524d\u3078\u306e<strong>CNAME\u3092\u5408\u6210<\/strong>\u3057\u3066\u52a0\u3048\u307e\u3059\u3002[1\u3001\u00a73.1]<\/p>\n<p>api.old.example.\u3068\u3044\u3046\u554f\u3044\u5408\u308f\u305b\u306a\u3089\u3001\u6982\u5ff5\u4e0a\u306f\u300cold.example. DNAME new.example.\u300d\u3068\u3044\u3046\u898f\u5247\u3068\u3001\u300capi.old.example. CNAME api.new.example.\u300d\u3068\u3044\u3046\u4eca\u56de\u306e\u5bfe\u5fdc\u304c\u4e00\u7dd2\u306b\u898b\u3048\u307e\u3059\u3002\u5f8c\u8005\u306f\u3001\u7ba1\u7406\u8005\u304c\u3059\u3079\u3066\u306e\u5b50\u5b6b\u540d\u306b\u3064\u3044\u3066\u500b\u5225\u306bCNAME\u3092\u767b\u9332\u3057\u305f\u8a3c\u62e0\u306b\u306f\u306a\u308a\u307e\u305b\u3093\u3002\u5fdc\u7b54\u3092\u4f5c\u308b\u969b\u306bDNAME\u304b\u3089\u5c0e\u3051\u308b\u305f\u3081\u3067\u3059\u3002<\/p>\n<p>\u540c\u7bc0\u3067\u306f\u3001\u5408\u6210CNAME\u306eTTL\u3092\u5bfe\u5fdc\u3059\u308bDNAME\u3068\u7b49\u3057\u304f\u3059\u308b\u3088\u3046\u5b9a\u3081\u3066\u3044\u307e\u3059\u3002TTL\u306f\u30ad\u30e3\u30c3\u30b7\u30e5\u3057\u3066\u4f7f\u3048\u308b\u6642\u9593\u3092\u4f1d\u3048\u308b\u5024\u3067\u3059\u3002\u30ad\u30e3\u30c3\u30b7\u30e5\u304b\u3089\u5408\u6210\u3059\u308b\u5834\u5408\u306f\u3001DNAME\u306e\u7d4c\u904e\u6642\u9593\u3092\u5dee\u3057\u5f15\u3044\u305fTTL\u306b\u5408\u308f\u305b\u308b\u3053\u3068\u304c\u63a8\u5968\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u53e4\u3044\u5b9f\u88c5\u306e\u5408\u6210CNAME\u304cTTL 0\u3092\u8fd4\u3059\u5834\u5408\u3082\u8003\u616e\u3055\u308c\u3001\u30ea\u30be\u30eb\u30d0\u30fc\u306f0\u3068DNAME\u76f8\u5f53\u306e\u5024\u306e\u53cc\u65b9\u3092\u6271\u3048\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3057\u305f\u304c\u3063\u3066\u3001\u89b3\u6e2c\u3057\u305fCNAME\u306eTTL\u3060\u3051\u304b\u3089\u3001\u624b\u4f5c\u696d\u3067\u767b\u9332\u3055\u308c\u305f\u30ec\u30b3\u30fc\u30c9\u304b\u3069\u3046\u304b\u3092\u65ad\u5b9a\u3067\u304d\u307e\u305b\u3093\u3002<\/p>\n<h2>\u8d77\u70b9\u306e\u60c5\u5831\u3068\u3001\u679d\u306e\u4e0b\u306e\u60c5\u5831\u306f\u540c\u3058\u5834\u6240\u306b\u7f6e\u3051\u306a\u3044<\/h2>\n<p>DNAME\u306e\u8a2d\u5b9a\u5143\u306b\u306f\u3001\u5171\u5b58\u306e\u5236\u7d04\u306b\u53cd\u3057\u306a\u3044\u307b\u304b\u306e\u7a2e\u985e\u306e\u30ec\u30b3\u30fc\u30c9\u3092\u7f6e\u3051\u307e\u3059\u3002\u305f\u3060\u3057\u3001\u540c\u3058\u540d\u524d\u306bCNAME\u3092\u7f6e\u304f\u3053\u3068\u306f\u3067\u304d\u305a\u3001DNAME\u3082\u4e00\u3064\u306b\u9650\u3089\u308c\u307e\u3059\u3002\u3055\u3089\u306bRFC 6672 \u00a72.4\u306f\u3001DNAME\u306e\u8a2d\u5b9a\u5143\u3088\u308a\u4e0b\u306b\u30ea\u30bd\u30fc\u30b9\u30ec\u30b3\u30fc\u30c9\u3092\u7f6e\u3044\u3066\u306f\u306a\u3089\u306a\u3044\u3068\u3057\u3066\u3044\u307e\u3059\u3002\u300c\u3053\u306e\u5b50\u3060\u3051\u306f\u65e7\u5074\u306eA\u3092\u512a\u5148\u3055\u305b\u308b\u300d\u3068\u3044\u3046\u4f8b\u5916\u306e\u4f5c\u308a\u65b9\u306b\u306f\u3067\u304d\u307e\u305b\u3093\u3002<\/p>\n<p>\u898f\u5247\u306b\u53cd\u3059\u308b\u4e0b\u4f4d\u30c7\u30fc\u30bf\u3092\u542b\u3080\u30be\u30fc\u30f3\u306f\u3001\u30b5\u30fc\u30d0\u30fc\u304c\u8aad\u307f\u8fbc\u307f\u3092\u62d2\u5426\u3057\u3066\u3082\u3088\u304f\u3001\u8aad\u307f\u8fbc\u3093\u3060\u3068\u3057\u3066\u3082DNAME\u306e\u4e0b\u306e\u30c7\u30fc\u30bf\u306f\u8986\u3044\u96a0\u3055\u308c\u307e\u3059\u3002\u79fb\u52d5\u5148\u306e\u540d\u524d\u3092\u8abf\u3079\u308b\u3053\u3068\u3067\u5185\u5bb9\u3092\u5f97\u308b\u305f\u3081\u3001\u79fb\u52d5\u5148\u306b\u5fc5\u8981\u306a\u60c5\u5831\u304c\u3042\u308b\u304b\u304c\u5225\u306e\u78ba\u8a8d\u70b9\u306b\u306a\u308a\u307e\u3059\u3002DNAME\u3092\u7f6e\u3044\u305f\u3060\u3051\u3067\u3001\u79fb\u52d5\u5148\u3078A\u3084AAAA\u306a\u3069\u306e\u5b9f\u30c7\u30fc\u30bf\u304c\u30b3\u30d4\u30fc\u3055\u308c\u308b\u308f\u3051\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n<p>\u30be\u30fc\u30f3\u306e\u9802\u70b9\u3001\u3064\u307e\u308a\u305d\u306e\u30be\u30fc\u30f3\u306e\u7ba1\u7406\u7bc4\u56f2\u306e\u8d77\u70b9\u3078DNAME\u3092\u7f6e\u304f\u5834\u5408\u3082\u3001\u305d\u3053\u3067\u5fc5\u8981\u306aSOA\u3084NS\u306f\u6b8b\u308a\u307e\u3059\u3002SOA\u306f\u30be\u30fc\u30f3\u306e\u7ba1\u7406\u60c5\u5831\u3001NS\u306f\u6a29\u5a01\u30b5\u30fc\u30d0\u30fc\u3092\u793a\u3057\u307e\u3059\u3002\u8d77\u70b9\u81ea\u8eab\u3092\u7f6e\u63db\u3057\u306a\u3044\u305f\u3081\u3001DNAME\u3060\u3051\u3067\u30be\u30fc\u30f3\u5168\u4f53\u3092\u5b8c\u5168\u306b\u5199\u3059\u3053\u3068\u306f\u3067\u304d\u307e\u305b\u3093\u3002[1\u3001\u00a72.3] \u914d\u4e0b\u3078\u306e\u6848\u5185\u304c\u6210\u529f\u3057\u3066\u3082\u3001\u8d77\u70b9\u3078\u306e\u554f\u3044\u5408\u308f\u305b\u307e\u3067\u540c\u3058\u7b54\u3048\u306b\u306a\u308b\u3068\u306f\u9650\u3089\u306a\u3044\u306e\u3067\u3059\u3002<\/p>\n<h2>\u79fb\u884c\u306e\u524d\u306b\u3001\u5bfe\u5fdc\u3059\u308b\u540d\u524d\u3068\u7d42\u70b9\u3092\u78ba\u304b\u3081\u308b<\/h2>\n<p>\u6bd4\u8f03\u3059\u308b\u3068\u304d\u306f\u3001\u307e\u305a\u8a2d\u5b9a\u5143\u3068\u540c\u3058\u540d\u524d\u3001\u305d\u306e\u4e00\u6bb5\u4e0b\u3001\u3055\u3089\u306b\u6df1\u3044\u540d\u524d\u3001\u4f3c\u305f\u7db4\u308a\u3067\u5bfe\u8c61\u5916\u306e\u540d\u524d\u3092\u5206\u3051\u307e\u3059\u3002\u6b21\u306b\u3001\u7f6e\u63db\u5f8c\u306e\u540d\u524d\u306b\u5fc5\u8981\u306a\u7a2e\u985e\u306e\u60c5\u5831\u304c\u3042\u308b\u304b\u3092\u8abf\u3079\u307e\u3059\u3002\u3053\u306e\u9806\u306b\u6574\u7406\u3059\u308b\u3068\u3001DNAME\u306e\u5bfe\u8c61\u5916\u306a\u306e\u304b\u3001\u7f6e\u63db\u306f\u3067\u304d\u305f\u304c\u884c\u304d\u5148\u306b\u60c5\u5831\u304c\u306a\u3044\u306e\u304b\u3092\u5207\u308a\u5206\u3051\u3089\u308c\u307e\u3059\u3002<\/p>\n<p>\u7f6e\u63db\u5148\u304c\u5143\u3078\u623b\u308b\u3088\u3046\u306a\u8a2d\u5b9a\u306a\u3089\u3001DNAME\u540c\u58eb\u3084CNAME\u3068\u306e\u7d44\u307f\u5408\u308f\u305b\u3067\u30eb\u30fc\u30d7\u3092\u4f5c\u308c\u307e\u3059\u3002\u307e\u305f\u3001\u5de6\u5074\u306b\u6b8b\u308b\u30e9\u30d9\u30eb\u3068\u8ee2\u9001\u5148\u3092\u5408\u308f\u305b\u3066DNS\u540d\u306e\u9577\u3055\u304c255\u30aa\u30af\u30c6\u30c3\u30c8\u3092\u8d85\u3048\u308b\u3068\u3001\u30b5\u30fc\u30d0\u30fc\u306fYXDOMAIN\u3092\u8fd4\u3057\u307e\u3059\u3002[1\u3001\u00a72.2] \u30aa\u30af\u30c6\u30c3\u30c8\u306f8\u30d3\u30c3\u30c8\u306e\u5358\u4f4d\u3067\u3042\u308a\u3001\u753b\u9762\u306b\u8868\u793a\u3057\u305f\u30c9\u30c3\u30c8\u4ed8\u304d\u6587\u5b57\u5217\u306e\u6587\u5b57\u6570\u3068\u306f\u5206\u3051\u3066\u6570\u3048\u307e\u3059\u3002\u72ec\u81ea\u8a08\u7b97\u3067\u306f\u5404\u30e9\u30d9\u30eb\u306e\u9577\u3055\u3092\u793a\u30591\u30aa\u30af\u30c6\u30c3\u30c8\u3068\u672b\u5c3e\u306e\u6839\u30e9\u30d9\u30eb\u3082\u6570\u3048\u3001\u7f6e\u63db\u5f8c\u306e\u9577\u3055\u304c255\u3068256\u306b\u306a\u308b\u5883\u754c\u4f8b\u3092\u7167\u5408\u3057\u307e\u3057\u305f\u3002\u3053\u308c\u306f\u4ed5\u69d8\u306e\u9577\u3055\u6761\u4ef6\u3092\u78ba\u304b\u3081\u305f\u8a08\u7b97\u3067\u3001\u5b9f\u969b\u306e\u30b5\u30fc\u30d0\u30fc\u304c\u8fd4\u3057\u305f\u5fdc\u7b54\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002<\/p>\n<p>\u672c\u7a3f\u306e\u6bd4\u8f03\u306fRFC 6672\u306eDNAME\u306e\u610f\u5473\u3068\u7f6e\u63db\u7bc4\u56f2\u306b\u9650\u5b9a\u3057\u3066\u3044\u307e\u3059\u3002\u88fd\u54c1\u3054\u3068\u306e\u8a2d\u5b9a\u753b\u9762\u3001\u30be\u30fc\u30f3\u306e\u8aad\u307f\u8fbc\u307f\u52d5\u4f5c\u3001DNSSEC\u691c\u8a3c\u3001\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u7d4c\u305f\u5207\u308a\u66ff\u308f\u308a\u306e\u6642\u9593\u307e\u3067\u306f\u5b9f\u6e2c\u3057\u3066\u3044\u307e\u305b\u3093\u3002\u540d\u524d\u306e\u6848\u5185\u5148\u3092\u5909\u3048\u3089\u308c\u308b\u3053\u3068\u3068\u3001\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u304c\u79fb\u884c\u5148\u3067\u6b63\u3057\u304f\u52d5\u304f\u3053\u3068\u3092\u5206\u3051\u3001\u4f7f\u3046\u5b9f\u88c5\u306e\u7248\u3068\u8a2d\u5b9a\u306b\u5fdc\u3058\u3066\u78ba\u304b\u3081\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<h2>\u51fa\u5178<\/h2>\n<ol>\n<li>RFC Editor, <a href=\"https:\/\/www.rfc-editor.org\/rfc\/rfc6672.html\">RFC 6672: DNAME Redirection in the DNS<\/a>\uff082012\u5e746\u6708\u520a\u884c\u3001Standards Track\u8868\u8a18\u306e\u672c\u6587\uff09\u3002\u00a7\u00a71\u30012.1\u20132.4\u30013.1\u3092\u53c2\u7167\u30022026\u5e7410\u670823\u65e5\u306b\u516c\u5f0f\u672c\u6587\u3092\u78ba\u8a8d\u3002Table 1\u306e\u7f6e\u63db\u6761\u4ef6\u3092\u8aad\u307f\u3001\u672c\u6587\u306e\u540d\u524d\u3068\u56f3\u3001\u5883\u754c\u8a08\u7b97\u306f\u72ec\u81ea\u306b\u4f5c\u6210\u3002\u73fe\u884c\u88fd\u54c1\u306e\u52d5\u4f5c\u691c\u8a3c\u3084\u898f\u683c\u72b6\u614b\u306e\u8ffd\u52a0\u8a8d\u5b9a\u3092\u610f\u5473\u3057\u306a\u3044\u3002<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>\u30c9\u30e1\u30a4\u30f3\u540d\u3092\u4e00\u3064\u305a\u3064\u5225\u540d\u3078\u5bfe\u5fdc\u3055\u305b\u308b\u4ee3\u308f\u308a\u306b\u3001\u540d\u524d\u306e\u6728\u306e\u4e00\u90e8\u5206\u3092\u307e\u3068\u3081\u3066\u5225\u306e\u5834\u6240\u3078\u5411\u3051\u305f\u3044\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002DNS\u306eDNAME\u306f\u3001\u305d\u306e\u305f\u3081\u306e\u30ec\u30b3\u30fc\u30c9\u3067\u3059\u3002\u305f\u3060\u3057\u3001\u8a2d\u5b9a\u3057\u305f\u540d\u524d\u81ea\u8eab\u3068\u3001\u305d\u306e\u4e0b\u306b\u3042\u308b\u540d\u524d\u3067\u306f\u6271\u3044\u304c\u9055\u3044\u307e\u3059\u3002\u3053\u306e [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":1379,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":true,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":false,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[29],"tags":[257],"class_list":["post-1381","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-communications-networking","tag-dns"],"jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/quantumsea.net\/wp-content\/uploads\/2026\/10\/qs-dns-dname-descendant-substitution-20261023-featured-e9378fe1ed56.png","_links":{"self":[{"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/posts\/1381","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/quantumsea.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1381"}],"version-history":[{"count":1,"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/posts\/1381\/revisions"}],"predecessor-version":[{"id":1383,"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/posts\/1381\/revisions\/1383"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/quantumsea.net\/index.php?rest_route=\/wp\/v2\/media\/1379"}],"wp:attachment":[{"href":"https:\/\/quantumsea.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1381"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/quantumsea.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1381"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/quantumsea.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1381"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}