{"id":27837,"date":"2025-05-03T18:02:43","date_gmt":"2025-05-03T11:02:43","guid":{"rendered":"https:\/\/interdata.vn\/blog\/?p=27837"},"modified":"2025-05-29T17:48:46","modified_gmt":"2025-05-29T10:48:46","slug":"ban-ghi-a-la-gi","status":"publish","type":"post","link":"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/","title":{"rendered":"B\u1ea3n ghi A l\u00e0 g\u00ec? Gi\u1ea3i th\u00edch DNS A Record chi ti\u1ebft &#038; D\u1ec5 hi\u1ec3u"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-white ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">N\u1ed8I DUNG<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Ban-ghi-A-A-Record-la-gi\" >B\u1ea3n ghi A (A Record) l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Ban-ghi-A-hoat-dong-nhu-the-nao\" >B\u1ea3n ghi A ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Quy-trinh-phan-giai-DNS-voi-ban-ghi-A\" >Quy tr\u00ecnh ph\u00e2n gi\u1ea3i DNS v\u1edbi b\u1ea3n ghi A<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Tai-sao-Ban-ghi-A-lai-quan-trong\" >T\u1ea1i sao B\u1ea3n ghi A l\u1ea1i quan tr\u1ecdng?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Dam-bao-Website-co-the-truy-cap-qua-ten-mien\" >\u0110\u1ea3m b\u1ea3o Website c\u00f3 th\u1ec3 truy c\u1eadp qua t\u00ean mi\u1ec1n<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Nen-tang-cho-cac-dich-vu-khac-Email-FTP%E2%80%A6\" >N\u1ec1n t\u1ea3ng cho c\u00e1c d\u1ecbch v\u1ee5 kh\u00e1c (Email, FTP,&#8230;)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Linh-hoat-trong-viec-quan-ly-va-thay-doi-may-chu\" >Linh ho\u1ea1t trong vi\u1ec7c qu\u1ea3n l\u00fd v\u00e0 thay \u0111\u1ed5i m\u00e1y ch\u1ee7<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Cau-truc-va-cac-thanh-phan-cua-ban-ghi-A\" >C\u1ea5u tr\u00fac v\u00e0 c\u00e1c th\u00e0nh ph\u1ea7n c\u1ee7a b\u1ea3n ghi A<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#HostName-Ten\" >Host\/Name (T\u00ean)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Type-Loai\" >Type (Lo\u1ea1i)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Value-Gia-tri\" >Value (Gi\u00e1 tr\u1ecb)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#TTL-Time-To-Live\" >TTL (Time To Live)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#So-sanh-ban-ghi-A-voi-cac-loai-ban-ghi-DNS-pho-bien-khac\" >So s\u00e1nh b\u1ea3n ghi A v\u1edbi c\u00e1c lo\u1ea1i b\u1ea3n ghi DNS ph\u1ed5 bi\u1ebfn kh\u00e1c<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Ban-ghi-A-vs-Ban-ghi-AAAA\" >B\u1ea3n ghi A vs. B\u1ea3n ghi AAAA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Ban-ghi-A-vs-Ban-ghi-CNAME\" >B\u1ea3n ghi A vs. B\u1ea3n ghi CNAME<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Ban-ghi-A-vs-Ban-ghi-MX\" >B\u1ea3n ghi A vs. B\u1ea3n ghi MX<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Cach-kiem-tra-ban-ghi-A-cua-mot-ten-mien\" >C\u00e1ch ki\u1ec3m tra b\u1ea3n ghi A c\u1ee7a m\u1ed9t t\u00ean mi\u1ec1n<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Su-dung-cong-cu-Online\" >S\u1eed d\u1ee5ng c\u00f4ng c\u1ee5 Online<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Su-dung-Command-PromptTerminal-Lenh-ping-nslookup\" >S\u1eed d\u1ee5ng Command Prompt\/Terminal (L\u1ec7nh ping, nslookup)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-20\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Huong-dan-co-ban-ve-Cau-hinh-Thay-doi-Ban-ghi-A\" >H\u01b0\u1edbng d\u1eabn c\u01a1 b\u1ea3n v\u1ec1 C\u1ea5u h\u00ecnh \/ Thay \u0111\u1ed5i B\u1ea3n ghi A<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-21\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Xac-dinh-dia-chi-IP-dich-can-tro-den\" >X\u00e1c \u0111\u1ecbnh \u0111\u1ecba ch\u1ec9 IP \u0111\u00edch c\u1ea7n tr\u1ecf \u0111\u1ebfn<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-22\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Truy-cap-khu-vuc-quan-ly-DNS\" >Truy c\u1eadp khu v\u1ef1c qu\u1ea3n l\u00fd DNS<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-23\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Thao-tac-ThemSuaXoa-ban-ghi-A-Dien-thong-tin-Host-Value-TTL\" >Thao t\u00e1c Th\u00eam\/S\u1eeda\/X\u00f3a b\u1ea3n ghi A (\u0110i\u1ec1n th\u00f4ng tin Host, Value, TTL)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-24\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Cau-hoi-thuong-gap-ve-ban-ghi-A-FAQ\" >C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 b\u1ea3n ghi A (FAQ)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-25\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#TTL-cho-ban-ghi-A-nen-dat-la-bao-nhieu\" >TTL cho b\u1ea3n ghi A n\u00ean \u0111\u1eb7t l\u00e0 bao nhi\u00eau?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-26\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Mot-ten-mien-co-the-co-nhieu-ban-ghi-A-khong\" >M\u1ed9t t\u00ean mi\u1ec1n c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u b\u1ea3n ghi A kh\u00f4ng?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-27\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Mat-bao-lau-de-thay-doi-ban-ghi-A-co-hieu-luc-DNS-Propagation\" >M\u1ea5t bao l\u00e2u \u0111\u1ec3 thay \u0111\u1ed5i b\u1ea3n ghi A c\u00f3 hi\u1ec7u l\u1ef1c? (DNS Propagation)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-28\" href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/#Su-khac-nhau-chinh-giua-ban-ghi-A-va-AAAA-la-gi\" >S\u1ef1 kh\u00e1c nhau ch\u00ednh gi\u1eefa b\u1ea3n ghi A v\u00e0 AAAA l\u00e0 g\u00ec?<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n\n<p>B\u1ea3n ghi A (A Record) l\u00e0 th\u00e0nh ph\u1ea7n n\u1ec1n t\u1ea3ng gi\u00fap Internet ho\u1ea1t \u0111\u1ed9ng nh\u01b0 ch\u00fang ta bi\u1ebft. N\u1ebfu kh\u00f4ng c\u00f3 b\u1ea3n ghi n\u00e0y, vi\u1ec7c truy c\u1eadp <a href=\"https:\/\/interdata.vn\/blog\/website-la-gi\/\">website<\/a> b\u1eb1ng <a href=\"https:\/\/interdata.vn\/blog\/domain-la-gi\/\">t\u00ean mi\u1ec1n<\/a> d\u1ec5 nh\u1edb nh\u01b0 <code>google.com<\/code> l\u00e0 kh\u00f4ng th\u1ec3. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd gi\u1ea3i th\u00edch chi ti\u1ebft b\u1ea3n ghi A l\u00e0 g\u00ec, c\u00e1ch ho\u1ea1t \u0111\u1ed9ng, t\u1ea7m quan tr\u1ecdng, c\u1ea5u tr\u00fac, c\u00e1ch ki\u1ec3m tra v\u00e0 c\u1ea5u h\u00ecnh c\u01a1 b\u1ea3n m\u1ed9t c\u00e1ch d\u1ec5 hi\u1ec3u nh\u1ea5t, \u0111\u1eb7c bi\u1ec7t h\u1eefu \u00edch cho ng\u01b0\u1eddi m\u1edbi b\u1eaft \u0111\u1ea7u qu\u1ea3n tr\u1ecb website.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Ban-ghi-A-A-Record-la-gi\"><\/span>B\u1ea3n ghi A (A Record) l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><a href=\"https:\/\/interdata.vn\/blog\/ban-ghi-a-la-gi\/\">B\u1ea3n ghi A<\/a> (vi\u1ebft t\u1eaft c\u1ee7a Address Record) l\u00e0 m\u1ed9t lo\u1ea1i b\u1ea3n ghi c\u01a1 b\u1ea3n v\u00e0 quan tr\u1ecdng nh\u1ea5t trong H\u1ec7 th\u1ed1ng ph\u00e2n gi\u1ea3i t\u00ean mi\u1ec1n &#8211; <strong>DNS (<a href=\"https:\/\/interdata.vn\/blog\/dns-la-gi\/\">Domain Name System<\/a>)<\/strong>. Nhi\u1ec7m v\u1ee5 ch\u00ednh c\u1ee7a b\u1ea3n ghi n\u00e0y l\u00e0 \u00e1nh x\u1ea1, hay &#8220;tr\u1ecf&#8221;, m\u1ed9t t\u00ean mi\u1ec1n ho\u1eb7c t\u00ean mi\u1ec1n ph\u1ee5 (<a href=\"https:\/\/interdata.vn\/blog\/subdomain-la-gi\/\">subdomain<\/a>) t\u1edbi <a href=\"https:\/\/interdata.vn\/blog\/dia-chi-ip-la-gi\/\">\u0111\u1ecba ch\u1ec9 IP<\/a> phi\u00ean b\u1ea3n 4 (<strong><a href=\"https:\/\/interdata.vn\/blog\/ipv4-la-gi\/\">IPv4<\/a> &#8211; Internet Protocol version 4<\/strong>) c\u1ee7a <a href=\"https:\/\/interdata.vn\/blog\/may-chu-server-la-gi\/\">m\u00e1y ch\u1ee7<\/a>.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A.jpg\" alt=\"B\u1ea3n ghi A\" width=\"750\" height=\"500\" class=\"aligncenter size-full wp-image-27840\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A.jpg 750w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-300x200.jpg 300w\" sizes=\"auto, (max-width: 750px) 100vw, 750px\" \/><\/p>\n<p>N\u00f3i \u0111\u01a1n gi\u1ea3n, b\u1ea3n ghi A gi\u1ed1ng nh\u01b0 m\u1ed9t m\u1ee5c trong danh b\u1ea1 kh\u1ed5ng l\u1ed3 c\u1ee7a Internet. M\u1ee5c n\u00e0y cho bi\u1ebft &#8220;\u0111\u1ecba ch\u1ec9 nh\u00e0&#8221; (\u0111\u1ecba ch\u1ec9 IP) c\u1ee5 th\u1ec3 c\u1ee7a m\u1ed9t &#8220;t\u00ean&#8221; (t\u00ean mi\u1ec1n) tr\u00ean m\u1ea1ng. \u0110i\u1ec1u n\u00e0y cho ph\u00e9p tr\u00ecnh duy\u1ec7t web t\u00ecm \u0111\u00fang m\u00e1y ch\u1ee7 ch\u1ee9a d\u1eef li\u1ec7u khi b\u1ea1n g\u00f5 t\u00ean mi\u1ec1n.<\/p>\n<p>\u0110\u1ecba ch\u1ec9 IP (Internet Protocol) l\u00e0 m\u1ed9t d\u00e3y s\u1ed1 \u0111\u1ecbnh danh duy nh\u1ea5t cho m\u1ed7i thi\u1ebft b\u1ecb (nh\u01b0 m\u00e1y ch\u1ee7) k\u1ebft n\u1ed1i v\u00e0o <a href=\"https:\/\/interdata.vn\/blog\/mang-internet\/\">m\u1ea1ng Internet<\/a>. B\u1ea3n ghi A li\u00ean k\u1ebft t\u00ean mi\u1ec1n d\u1ec5 nh\u1edb v\u1edbi \u0111\u1ecba ch\u1ec9 IPv4 ph\u1ee9c t\u1ea1p, th\u01b0\u1eddng c\u00f3 d\u1ea1ng b\u1ed1n c\u1ee5m s\u1ed1 c\u00e1ch nhau b\u1edfi d\u1ea5u ch\u1ea5m, v\u00ed d\u1ee5: <code>192.0.2.1<\/code>.<\/p>\n<p>M\u1ed9t v\u00ed d\u1ee5 c\u1ee5 th\u1ec3 v\u1ec1 c\u1ea5u h\u00ecnh b\u1ea3n ghi A trong file c\u1ea5u h\u00ecnh DNS c\u00f3 th\u1ec3 l\u00e0: <code>yourdomain.com. IN A 192.0.2.1<\/code>. D\u00f2ng n\u00e0y ch\u1ec9 r\u00f5 r\u1eb1ng t\u00ean mi\u1ec1n <code>yourdomain.com<\/code> \u0111\u01b0\u1ee3c ph\u00e2n gi\u1ea3i th\u00e0nh \u0111\u1ecba ch\u1ec9 IPv4 <code>192.0.2.1<\/code>.<\/p>\n<p>Vi\u1ec7c hi\u1ec3u v\u00e0 c\u1ea5u h\u00ecnh ch\u00ednh x\u00e1c b\u1ea3n ghi A l\u00e0 c\u1ef1c k\u1ef3 c\u1ea7n thi\u1ebft. B\u1ea5t k\u1ef3 sai s\u00f3t n\u00e0o trong b\u1ea3n ghi n\u00e0y \u0111\u1ec1u c\u00f3 th\u1ec3 khi\u1ebfn website ho\u1eb7c d\u1ecbch v\u1ee5 tr\u1ef1c tuy\u1ebfn c\u1ee7a b\u1ea1n kh\u00f4ng th\u1ec3 truy c\u1eadp \u0111\u01b0\u1ee3c th\u00f4ng qua t\u00ean mi\u1ec1n, g\u00e2y \u1ea3nh h\u01b0\u1edfng ti\u00eau c\u1ef1c.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Ban-ghi-A-hoat-dong-nhu-the-nao\"><\/span>B\u1ea3n ghi A ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>B\u1ea3n ghi A \u0111\u00f3ng vai tr\u00f2 trung t\u00e2m trong qu\u00e1 tr\u00ecnh <strong>ph\u00e2n gi\u1ea3i t\u00ean mi\u1ec1n (DNS resolution)<\/strong>. \u0110\u00e2y l\u00e0 qu\u00e1 tr\u00ecnh <a href=\"https:\/\/interdata.vn\/blog\/domain-migration-la-gi\/\">chuy\u1ec3n \u0111\u1ed5i t\u00ean mi\u1ec1n<\/a> m\u00e0 con ng\u01b0\u1eddi d\u1ec5 \u0111\u1ecdc (v\u00ed d\u1ee5: <code><a href=\"https:\/\/interdata.vn\/blog\/world-wide-web\/\">www<\/a>.google.com<\/code>) th\u00e0nh \u0111\u1ecba ch\u1ec9 IP m\u00e0 m\u00e1y t\u00ednh c\u00f3 th\u1ec3 hi\u1ec3u (<code>172.217.160.142<\/code>).<\/p>\n<p>Khi b\u1ea1n nh\u1eadp m\u1ed9t t\u00ean mi\u1ec1n v\u00e0o thanh \u0111\u1ecba ch\u1ec9 c\u1ee7a <strong>tr\u00ecnh duy\u1ec7t web (web browser)<\/strong> v\u00e0 nh\u1ea5n Enter, m\u1ed9t chu\u1ed7i c\u00e1c <a href=\"https:\/\/interdata.vn\/blog\/query-la-gi\/\">truy v\u1ea5n<\/a> DNS s\u1ebd di\u1ec5n ra ph\u00eda sau h\u1eadu tr\u01b0\u1eddng \u0111\u1ec3 t\u00ecm ra \u0111\u1ecba ch\u1ec9 IP t\u01b0\u01a1ng \u1ee9ng. B\u1ea3n ghi A ch\u00ednh l\u00e0 \u0111\u00edch \u0111\u1ebfn cu\u1ed1i c\u00f9ng c\u1ee7a truy v\u1ea5n n\u00e0y \u0111\u1ed1i v\u1edbi \u0111\u1ecba ch\u1ec9 IPv4.<\/p>\n<p>H\u00e3y t\u01b0\u1edfng t\u01b0\u1ee3ng b\u1ea1n mu\u1ed1n g\u1ecdi \u0111i\u1ec7n cho m\u1ed9t ng\u01b0\u1eddi b\u1ea1n (truy c\u1eadp website). B\u1ea1n bi\u1ebft t\u00ean ng\u01b0\u1eddi b\u1ea1n \u0111\u00f3 (t\u00ean mi\u1ec1n), nh\u01b0ng b\u1ea1n c\u1ea7n s\u1ed1 \u0111i\u1ec7n tho\u1ea1i (\u0111\u1ecba ch\u1ec9 IP) \u0111\u1ec3 k\u1ebft n\u1ed1i. H\u1ec7 th\u1ed1ng DNS ho\u1ea1t \u0111\u1ed9ng nh\u01b0 m\u1ed9t cu\u1ed1n danh b\u1ea1 kh\u1ed5ng l\u1ed3.<\/p>\n<p>B\u1ea1n (tr\u00ecnh duy\u1ec7t) h\u1ecfi t\u1ed5ng \u0111\u00e0i (m\u00e1y ch\u1ee7 DNS) s\u1ed1 \u0111i\u1ec7n tho\u1ea1i c\u1ee7a ng\u01b0\u1eddi b\u1ea1n (t\u00ean mi\u1ec1n). T\u1ed5ng \u0111\u00e0i tra c\u1ee9u trong danh b\u1ea1 (c\u01a1 s\u1edf d\u1eef li\u1ec7u DNS) v\u00e0 t\u00ecm th\u1ea5y m\u1ee5c ghi t\u00ean ng\u01b0\u1eddi b\u1ea1n c\u00f9ng s\u1ed1 \u0111i\u1ec7n tho\u1ea1i (b\u1ea3n ghi A ch\u1ee9a \u0111\u1ecba ch\u1ec9 IP). T\u1ed5ng \u0111\u00e0i tr\u1ea3 v\u1ec1 s\u1ed1 \u0111i\u1ec7n tho\u1ea1i \u0111\u00f3 cho b\u1ea1n.<\/p>\n<p>Cu\u1ed1i c\u00f9ng, b\u1ea1n s\u1eed d\u1ee5ng s\u1ed1 \u0111i\u1ec7n tho\u1ea1i \u0111\u01b0\u1ee3c cung c\u1ea5p (\u0111\u1ecba ch\u1ec9 IP) \u0111\u1ec3 th\u1ef1c hi\u1ec7n cu\u1ed9c g\u1ecdi (k\u1ebft n\u1ed1i \u0111\u1ebfn <a href=\"https:\/\/interdata.vn\/blog\/web-server\/\">m\u00e1y ch\u1ee7 web<\/a>). B\u1ea3n ghi A ch\u00ednh l\u00e0 th\u00f4ng tin c\u1ed1t l\u00f5i trong &#8220;m\u1ee5c danh b\u1ea1&#8221; \u0111\u00f3.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-01.jpg\" alt=\"B\u1ea3n ghi A 01\" width=\"750\" height=\"375\" class=\"aligncenter size-full wp-image-27838\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-01.jpg 750w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-01-300x150.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-01-360x180.jpg 360w\" sizes=\"auto, (max-width: 750px) 100vw, 750px\" \/><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Quy-trinh-phan-giai-DNS-voi-ban-ghi-A\"><\/span>Quy tr\u00ecnh ph\u00e2n gi\u1ea3i DNS v\u1edbi b\u1ea3n ghi A<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Qu\u00e1 tr\u00ecnh ph\u00e2n gi\u1ea3i t\u00ean mi\u1ec1n s\u1eed d\u1ee5ng b\u1ea3n ghi A di\u1ec5n ra qua nhi\u1ec1u b\u01b0\u1edbc, nh\u01b0ng c\u00f3 th\u1ec3 t\u00f3m t\u1eaft \u0111\u01a1n gi\u1ea3n nh\u01b0 sau:<\/p>\n<ol>\n<li><strong>Y\u00eau c\u1ea7u ng\u01b0\u1eddi d\u00f9ng:<\/strong> B\u1ea1n nh\u1eadp t\u00ean mi\u1ec1n (v\u00ed d\u1ee5: <code>example.com<\/code>) v\u00e0o tr\u00ecnh duy\u1ec7t.<\/li>\n<li><strong>Ki\u1ec3m tra Cache:<\/strong> Tr\u00ecnh duy\u1ec7t v\u00e0 <a href=\"https:\/\/interdata.vn\/blog\/he-dieu-hanh\/\">h\u1ec7 \u0111i\u1ec1u h\u00e0nh<\/a> ki\u1ec3m tra <a href=\"https:\/\/interdata.vn\/blog\/bo-nho-dem-la-gi\/\">b\u1ed9 nh\u1edb \u0111\u1ec7m<\/a> (cache) c\u1ee5c b\u1ed9 xem c\u00f3 l\u01b0u \u0111\u1ecba ch\u1ec9 IP c\u1ee7a t\u00ean mi\u1ec1n n\u00e0y t\u1eeb l\u1ea7n truy c\u1eadp tr\u01b0\u1edbc kh\u00f4ng. N\u1ebfu c\u00f3, \u0111\u1ecba ch\u1ec9 IP \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ngay.<\/li>\n<li><strong>Truy v\u1ea5n Recursive DNS:<\/strong> N\u1ebfu kh\u00f4ng c\u00f3 trong cache, m\u00e1y t\u00ednh g\u1eedi y\u00eau c\u1ea7u \u0111\u1ebfn <strong>M\u00e1y ch\u1ee7 DNS <a href=\"https:\/\/interdata.vn\/blog\/de-quy-la-gi\/\">\u0111\u1ec7 quy<\/a> (Recursive DNS Server)<\/strong>, th\u01b0\u1eddng do Nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 Internet (ISP) qu\u1ea3n l\u00fd.<\/li>\n<li><strong>Truy v\u1ea5n Root Server:<\/strong> M\u00e1y ch\u1ee7 \u0111\u1ec7 quy h\u1ecfi <strong>M\u00e1y ch\u1ee7 DNS g\u1ed1c (Root Server)<\/strong> \u0111\u1ec3 bi\u1ebft m\u00e1y ch\u1ee7 n\u00e0o qu\u1ea3n l\u00fd t\u00ean mi\u1ec1n c\u1ea5p cao nh\u1ea5t (<a href=\"https:\/\/interdata.vn\/blog\/top-level-domain\/\">Top-Level Domain<\/a> &#8211; TLD) nh\u01b0 <code><a href=\"https:\/\/interdata.vn\/blog\/ten-mien-com-la-gi\/\">.com<\/a><\/code>.<\/li>\n<li><strong>Truy v\u1ea5n TLD Server:<\/strong> M\u00e1y ch\u1ee7 \u0111\u1ec7 quy ti\u1ebfp t\u1ee5c h\u1ecfi m\u00e1y ch\u1ee7 TLD (<code>.com<\/code>) \u0111\u1ec3 bi\u1ebft m\u00e1y ch\u1ee7 n\u00e0o ch\u1ecbu tr\u00e1ch nhi\u1ec7m cho t\u00ean mi\u1ec1n c\u1ee5 th\u1ec3 (<code>example.com<\/code>). \u0110\u00e2y l\u00e0 <strong>M\u00e1y ch\u1ee7 DNS c\u00f3 th\u1ea9m quy\u1ec1n (Authoritative <a href=\"https:\/\/interdata.vn\/blog\/name-server-la-gi\/\">Name Server<\/a>)<\/strong>.<\/li>\n<li><strong>Truy v\u1ea5n Authoritative Server:<\/strong> M\u00e1y ch\u1ee7 \u0111\u1ec7 quy h\u1ecfi M\u00e1y ch\u1ee7 DNS c\u00f3 th\u1ea9m quy\u1ec1n v\u1ec1 b\u1ea3n ghi A c\u1ee7a <code>example.com<\/code>.<\/li>\n<li><strong>Nh\u1eadn b\u1ea3n ghi A:<\/strong> M\u00e1y ch\u1ee7 DNS c\u00f3 th\u1ea9m quy\u1ec1n t\u00ecm b\u1ea3n ghi A trong d\u1eef li\u1ec7u c\u1ee7a m\u00ecnh v\u00e0 tr\u1ea3 v\u1ec1 \u0111\u1ecba ch\u1ec9 IPv4 (v\u00ed d\u1ee5: <code>192.0.2.1<\/code>) cho m\u00e1y ch\u1ee7 \u0111\u1ec7 quy.<\/li>\n<li><strong>Tr\u1ea3 k\u1ebft qu\u1ea3 v\u1ec1 tr\u00ecnh duy\u1ec7t:<\/strong> M\u00e1y ch\u1ee7 \u0111\u1ec7 quy l\u01b0u k\u1ebft qu\u1ea3 v\u00e0o cache v\u00e0 g\u1eedi \u0111\u1ecba ch\u1ec9 IP v\u1ec1 cho tr\u00ecnh duy\u1ec7t c\u1ee7a b\u1ea1n.<\/li>\n<li><strong>K\u1ebft n\u1ed1i:<\/strong> Tr\u00ecnh duy\u1ec7t s\u1eed d\u1ee5ng \u0111\u1ecba ch\u1ec9 IP n\u00e0y \u0111\u1ec3 thi\u1ebft l\u1eadp k\u1ebft n\u1ed1i tr\u1ef1c ti\u1ebfp \u0111\u1ebfn m\u00e1y ch\u1ee7 web ch\u1ee9a n\u1ed9i dung c\u1ee7a <code>example.com<\/code>.<\/li>\n<\/ol>\n<p>To\u00e0n b\u1ed9 qu\u00e1 tr\u00ecnh n\u00e0y th\u01b0\u1eddng ch\u1ec9 di\u1ec5n ra trong mili gi\u00e2y, \u0111\u1ea3m b\u1ea3o tr\u1ea3i nghi\u1ec7m truy c\u1eadp web m\u01b0\u1ee3t m\u00e0.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tai-sao-Ban-ghi-A-lai-quan-trong\"><\/span>T\u1ea1i sao B\u1ea3n ghi A l\u1ea1i quan tr\u1ecdng?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>B\u1ea3n ghi A kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t ph\u1ea7n k\u1ef9 thu\u1eadt c\u1ee7a DNS; b\u1ea3n ghi n\u00e0y l\u00e0 y\u1ebfu t\u1ed1 n\u1ec1n t\u1ea3ng \u0111\u1ea3m b\u1ea3o s\u1ef1 hi\u1ec7n di\u1ec7n v\u00e0 kh\u1ea3 n\u0103ng truy c\u1eadp c\u1ee7a b\u1ea1n tr\u00ean Internet. N\u1ebfu kh\u00f4ng c\u00f3 b\u1ea3n ghi A ch\u00ednh x\u00e1c, t\u00ean mi\u1ec1n c\u1ee7a b\u1ea1n tr\u1edf n\u00ean v\u00f4 d\u1ee5ng.<\/p>\n<p>T\u1ea7m quan tr\u1ecdng c\u1ee7a b\u1ea3n ghi A th\u1ec3 hi\u1ec7n qua c\u00e1c kh\u00eda c\u1ea1nh sau:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Dam-bao-Website-co-the-truy-cap-qua-ten-mien\"><\/span>\u0110\u1ea3m b\u1ea3o Website c\u00f3 th\u1ec3 truy c\u1eadp qua t\u00ean mi\u1ec1n<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 vai tr\u00f2 c\u01a1 b\u1ea3n v\u00e0 quan tr\u1ecdng nh\u1ea5t. B\u1ea3n ghi A li\u00ean k\u1ebft t\u00ean mi\u1ec1n th\u00e2n thi\u1ec7n v\u1edbi ng\u01b0\u1eddi d\u00f9ng (d\u1ec5 nh\u1edb, d\u1ec5 g\u00f5) v\u1edbi \u0111\u1ecba ch\u1ec9 IP k\u1ef9 thu\u1eadt c\u1ee7a m\u00e1y ch\u1ee7. N\u1ebfu kh\u00f4ng c\u00f3 li\u00ean k\u1ebft n\u00e0y, kh\u00f4ng ai c\u00f3 th\u1ec3 truy c\u1eadp website c\u1ee7a b\u1ea1n b\u1eb1ng c\u00e1ch g\u00f5 t\u00ean mi\u1ec1n v\u00e0o tr\u00ecnh duy\u1ec7t.<\/p>\n<p>Khi b\u1ea3n ghi A b\u1ecb thi\u1ebfu ho\u1eb7c tr\u1ecf sai \u0111\u1ecba ch\u1ec9 IP, ng\u01b0\u1eddi d\u00f9ng s\u1ebd nh\u1eadn th\u00f4ng b\u00e1o l\u1ed7i nh\u01b0 &#8220;Server not found&#8221; ho\u1eb7c &#8220;This site can\u2019t be reached&#8221;. \u0110i\u1ec1u n\u00e0y tr\u1ef1c ti\u1ebfp \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn l\u01b0u l\u01b0\u1ee3ng truy c\u1eadp, uy t\u00edn v\u00e0 ho\u1ea1t \u0111\u1ed9ng kinh doanh (n\u1ebfu c\u00f3).<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Nen-tang-cho-cac-dich-vu-khac-Email-FTP%E2%80%A6\"><\/span>N\u1ec1n t\u1ea3ng cho c\u00e1c d\u1ecbch v\u1ee5 kh\u00e1c (Email, FTP,&#8230;)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1eb7c d\u00f9 c\u00f3 c\u00e1c lo\u1ea1i b\u1ea3n ghi DNS kh\u00e1c d\u00e0nh ri\u00eang cho email (MX) ho\u1eb7c c\u00e1c m\u1ee5c \u0111\u00edch kh\u00e1c, nhi\u1ec1u d\u1ecbch v\u1ee5 v\u1eabn d\u1ef1a v\u00e0o b\u1ea3n ghi A c\u1ee7a t\u00ean mi\u1ec1n g\u1ed1c ho\u1eb7c t\u00ean mi\u1ec1n ph\u1ee5. V\u00ed d\u1ee5, \u0111\u1ec3 c\u1ea5u h\u00ecnh email theo t\u00ean mi\u1ec1n ri\u00eang (<code>info@yourdomain.com<\/code>), <a href=\"https:\/\/interdata.vn\/blog\/ban-ghi-mx-la-gi\/\">b\u1ea3n ghi MX<\/a> c\u1ea7n bi\u1ebft m\u00e1y ch\u1ee7 mail n\u00e0o x\u1eed l\u00fd th\u01b0.<\/p>\n<p>M\u00e1y ch\u1ee7 mail n\u00e0y (v\u00ed d\u1ee5: <code>mail.yourdomain.com<\/code>) c\u0169ng c\u1ea7n c\u00f3 b\u1ea3n ghi A (ho\u1eb7c AAAA) tr\u1ecf \u0111\u1ebfn \u0111\u1ecba ch\u1ec9 IP c\u1ee7a m\u00e1y ch\u1ee7 mail \u0111\u00f3. T\u01b0\u01a1ng t\u1ef1, c\u00e1c d\u1ecbch v\u1ee5 nh\u01b0 FTP (<a href=\"https:\/\/interdata.vn\/blog\/ftp-la-gi\/\">File Transfer Protocol<\/a>) ho\u1eb7c c\u00e1c <a href=\"https:\/\/interdata.vn\/blog\/web-application-la-gi\/\">\u1ee9ng d\u1ee5ng web<\/a> kh\u00e1c ch\u1ea1y tr\u00ean subdomain c\u0169ng c\u1ea7n b\u1ea3n ghi A \u0111\u1ec3 \u0111\u1ecbnh v\u1ecb \u0111\u00fang m\u00e1y ch\u1ee7.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Linh-hoat-trong-viec-quan-ly-va-thay-doi-may-chu\"><\/span>Linh ho\u1ea1t trong vi\u1ec7c qu\u1ea3n l\u00fd v\u00e0 thay \u0111\u1ed5i m\u00e1y ch\u1ee7<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>B\u1ea3n ghi A mang l\u1ea1i s\u1ef1 linh ho\u1ea1t l\u1edbn khi b\u1ea1n c\u1ea7n thay \u0111\u1ed5i nh\u00e0 cung c\u1ea5p <strong>hosting (d\u1ecbch v\u1ee5 l\u01b0u tr\u1eef web)<\/strong> ho\u1eb7c di chuy\u1ec3n website sang m\u1ed9t <strong>m\u00e1y ch\u1ee7 (server)<\/strong> m\u1edbi c\u00f3 \u0111\u1ecba ch\u1ec9 IP kh\u00e1c.<\/p>\n<p>Thay v\u00ec ph\u1ea3i thay \u0111\u1ed5i t\u00ean mi\u1ec1n (\u0111i\u1ec1u n\u00e0y g\u1ea7n nh\u01b0 kh\u00f4ng kh\u1ea3 thi v\u00e0 \u1ea3nh h\u01b0\u1edfng l\u1edbn \u0111\u1ebfn th\u01b0\u01a1ng hi\u1ec7u, <a href=\"https:\/\/interdata.vn\/blog\/seo-la-gi\/\">SEO<\/a>), b\u1ea1n ch\u1ec9 c\u1ea7n c\u1eadp nh\u1eadt gi\u00e1 tr\u1ecb \u0111\u1ecba ch\u1ec9 IP trong b\u1ea3n ghi A c\u1ee7a t\u00ean mi\u1ec1n \u0111\u00f3 t\u1ea1i trang qu\u1ea3n l\u00fd DNS. T\u00ean mi\u1ec1n v\u1eabn gi\u1eef nguy\u00ean, ch\u1ec9 c\u00f3 &#8220;\u0111\u1ecba ch\u1ec9 nh\u00e0&#8221; ph\u00eda sau thay \u0111\u1ed5i.<\/p>\n<p>S\u1ef1 t\u00e1ch bi\u1ec7t gi\u1eefa t\u00ean mi\u1ec1n v\u00e0 \u0111\u1ecba ch\u1ec9 IP th\u00f4ng qua b\u1ea3n ghi A gi\u00fap vi\u1ec7c qu\u1ea3n tr\u1ecb h\u1ea1 t\u1ea7ng web tr\u1edf n\u00ean d\u1ec5 d\u00e0ng v\u00e0 \u00edt r\u1ee7i ro h\u01a1n nhi\u1ec1u.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-02.jpg\" alt=\"B\u1ea3n ghi A 02\" width=\"750\" height=\"375\" class=\"aligncenter size-full wp-image-27842\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-02.jpg 750w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-02-300x150.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-02-360x180.jpg 360w\" sizes=\"auto, (max-width: 750px) 100vw, 750px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cau-truc-va-cac-thanh-phan-cua-ban-ghi-A\"><\/span>C\u1ea5u tr\u00fac v\u00e0 c\u00e1c th\u00e0nh ph\u1ea7n c\u1ee7a b\u1ea3n ghi A<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>M\u1ed9t b\u1ea3n ghi A ti\u00eau chu\u1ea9n bao g\u1ed3m m\u1ed9t s\u1ed1 tr\u01b0\u1eddng th\u00f4ng tin quan tr\u1ecdng. Khi b\u1ea1n th\u00eam ho\u1eb7c ch\u1ec9nh s\u1eeda b\u1ea3n ghi A trong giao di\u1ec7n qu\u1ea3n l\u00fd DNS, b\u1ea1n th\u01b0\u1eddng s\u1ebd l\u00e0m vi\u1ec7c v\u1edbi c\u00e1c th\u00e0nh ph\u1ea7n sau:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"HostName-Ten\"><\/span>Host\/Name (T\u00ean)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 ph\u1ea7n x\u00e1c \u0111\u1ecbnh t\u00ean mi\u1ec1n ho\u1eb7c t\u00ean mi\u1ec1n ph\u1ee5 m\u00e0 b\u1ea1n mu\u1ed1n tr\u1ecf \u0111\u1ebfn \u0111\u1ecba ch\u1ec9 IP.<\/p>\n<ul>\n<li>N\u1ebfu b\u1ea1n mu\u1ed1n <a href=\"https:\/\/interdata.vn\/blog\/cach-tro-ten-mien-ve-hosting\/\">tr\u1ecf t\u00ean mi\u1ec1n<\/a> g\u1ed1c (v\u00ed d\u1ee5: <code>yourdomain.com<\/code>), b\u1ea1n th\u01b0\u1eddng nh\u1eadp <code>@<\/code> ho\u1eb7c \u0111\u1ec3 tr\u1ed1ng, t\u00f9y thu\u1ed9c v\u00e0o giao di\u1ec7n qu\u1ea3n l\u00fd DNS c\u1ee7a nh\u00e0 cung c\u1ea5p.<\/li>\n<li>N\u1ebfu b\u1ea1n mu\u1ed1n tr\u1ecf m\u1ed9t t\u00ean mi\u1ec1n ph\u1ee5 (subdomain, v\u00ed d\u1ee5: <code><a href=\"https:\/\/interdata.vn\/blog\/blog-la-gi\/\">blog<\/a>.yourdomain.com<\/code>), b\u1ea1n s\u1ebd nh\u1eadp t\u00ean c\u1ee7a subdomain \u0111\u00f3 (<code>blog<\/code>).<\/li>\n<li>K\u00fd t\u1ef1 <code>*<\/code> \u0111\u00f4i khi \u0111\u01b0\u1ee3c d\u00f9ng l\u00e0m k\u00fd t\u1ef1 \u0111\u1ea1i di\u1ec7n (wildcard), ngh\u0129a l\u00e0 \u00e1p d\u1ee5ng cho t\u1ea5t c\u1ea3 c\u00e1c subdomain kh\u00f4ng \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a c\u1ee5 th\u1ec3.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Type-Loai\"><\/span>Type (Lo\u1ea1i)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Tr\u01b0\u1eddng n\u00e0y x\u00e1c \u0111\u1ecbnh lo\u1ea1i b\u1ea3n ghi DNS. \u0110\u1ed1i v\u1edbi b\u1ea3n ghi A, gi\u00e1 tr\u1ecb c\u1ee7a tr\u01b0\u1eddng n\u00e0y lu\u00f4n lu\u00f4n l\u00e0 <code>A<\/code>. H\u1ec7 th\u1ed1ng DNS d\u1ef1a v\u00e0o lo\u1ea1i b\u1ea3n ghi \u0111\u1ec3 bi\u1ebft c\u00e1ch di\u1ec5n gi\u1ea3i gi\u00e1 tr\u1ecb \u0111i k\u00e8m.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Value-Gia-tri\"><\/span>Value (Gi\u00e1 tr\u1ecb)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 th\u00e0nh ph\u1ea7n quan tr\u1ecdng nh\u1ea5t c\u1ee7a b\u1ea3n ghi A. Gi\u00e1 tr\u1ecb n\u00e0y <strong>b\u1eaft bu\u1ed9c ph\u1ea3i l\u00e0 m\u1ed9t \u0111\u1ecba ch\u1ec9 IPv4 h\u1ee3p l\u1ec7<\/strong> c\u1ee7a m\u00e1y ch\u1ee7 m\u00e0 b\u1ea1n mu\u1ed1n t\u00ean mi\u1ec1n ho\u1eb7c t\u00ean mi\u1ec1n ph\u1ee5 tr\u1ecf t\u1edbi.<\/p>\n<p>\u0110\u1ecba ch\u1ec9 IPv4 c\u00f3 \u0111\u1ecbnh d\u1ea1ng g\u1ed3m b\u1ed1n c\u1ee5m s\u1ed1 (octet), m\u1ed7i c\u1ee5m c\u00f3 gi\u00e1 tr\u1ecb t\u1eeb 0 \u0111\u1ebfn 255, c\u00e1ch nhau b\u1edfi d\u1ea5u ch\u1ea5m. V\u00ed d\u1ee5: <code>203.0.113.1<\/code>. Nh\u1eadp sai \u0111\u1ecbnh d\u1ea1ng ho\u1eb7c sai \u0111\u1ecba ch\u1ec9 IP s\u1ebd khi\u1ebfn b\u1ea3n ghi kh\u00f4ng ho\u1ea1t \u0111\u1ed9ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"TTL-Time-To-Live\"><\/span>TTL (Time To Live)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>TTL (<a href=\"https:\/\/interdata.vn\/blog\/ttl-la-gi\/\">Time To Live<\/a>)<\/strong> l\u00e0 m\u1ed9t gi\u00e1 tr\u1ecb s\u1ed1, t\u00ednh b\u1eb1ng gi\u00e2y, quy \u0111\u1ecbnh kho\u1ea3ng th\u1eddi gian m\u00e0 c\u00e1c m\u00e1y ch\u1ee7 DNS kh\u00e1c (nh\u01b0 m\u00e1y ch\u1ee7 DNS \u0111\u1ec7 quy c\u1ee7a ISP) \u0111\u01b0\u1ee3c ph\u00e9p l\u01b0u tr\u1eef (cache) th\u00f4ng tin c\u1ee7a b\u1ea3n ghi n\u00e0y.<\/p>\n<p>Sau khi h\u1ebft th\u1eddi gian TTL, c\u00e1c m\u00e1y ch\u1ee7 DNS ph\u1ea3i truy v\u1ea5n l\u1ea1i m\u00e1y ch\u1ee7 DNS c\u00f3 th\u1ea9m quy\u1ec1n \u0111\u1ec3 l\u1ea5y th\u00f4ng tin m\u1edbi nh\u1ea5t. TTL \u1ea3nh h\u01b0\u1edfng tr\u1ef1c ti\u1ebfp \u0111\u1ebfn t\u1ed1c \u0111\u1ed9 c\u1eadp nh\u1eadt thay \u0111\u1ed5i DNS tr\u00ean to\u00e0n c\u1ea7u, c\u00f2n g\u1ecdi l\u00e0 <strong>DNS propagation<\/strong>.<\/p>\n<p>TTL ph\u1ed5 bi\u1ebfn th\u01b0\u1eddng l\u00e0 3600 gi\u00e2y (1 gi\u1edd), 14400 gi\u00e2y (4 gi\u1edd), ho\u1eb7c 86400 gi\u00e2y (24 gi\u1edd). TTL th\u1ea5p h\u01a1n (v\u00ed d\u1ee5: 300 gi\u00e2y = 5 ph\u00fat) gi\u00fap thay \u0111\u1ed5i DNS c\u1eadp nh\u1eadt nhanh h\u01a1n, nh\u01b0ng t\u0103ng t\u1ea3i cho m\u00e1y ch\u1ee7 DNS c\u00f3 th\u1ea9m quy\u1ec1n.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"So-sanh-ban-ghi-A-voi-cac-loai-ban-ghi-DNS-pho-bien-khac\"><\/span>So s\u00e1nh b\u1ea3n ghi A v\u1edbi c\u00e1c lo\u1ea1i b\u1ea3n ghi DNS ph\u1ed5 bi\u1ebfn kh\u00e1c<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>H\u1ec7 th\u1ed1ng DNS c\u00f3 nhi\u1ec1u lo\u1ea1i b\u1ea3n ghi kh\u00e1c nhau, m\u1ed7i lo\u1ea1i ph\u1ee5c v\u1ee5 m\u1ed9t m\u1ee5c \u0111\u00edch ri\u00eang. Vi\u1ec7c ph\u00e2n bi\u1ec7t b\u1ea3n ghi A v\u1edbi c\u00e1c lo\u1ea1i ph\u1ed5 bi\u1ebfn kh\u00e1c l\u00e0 r\u1ea5t quan tr\u1ecdng \u0111\u1ec3 tr\u00e1nh nh\u1ea7m l\u1eabn khi c\u1ea5u h\u00ecnh:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Ban-ghi-A-vs-Ban-ghi-AAAA\"><\/span>B\u1ea3n ghi A vs. B\u1ea3n ghi AAAA<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li><strong>B\u1ea3n ghi A (Address Record):<\/strong> \u00c1nh x\u1ea1 t\u00ean mi\u1ec1n t\u1edbi \u0111\u1ecba ch\u1ec9 <strong>IPv4<\/strong>.<\/li>\n<li><strong>B\u1ea3n ghi AAAA (Quad A Record):<\/strong> \u00c1nh x\u1ea1 t\u00ean mi\u1ec1n t\u1edbi \u0111\u1ecba ch\u1ec9 <strong><a href=\"https:\/\/interdata.vn\/blog\/ipv6-la-gi\/\">IPv6<\/a> (Internet Protocol version 6)<\/strong>. IPv6 l\u00e0 phi\u00ean b\u1ea3n giao th\u1ee9c Internet m\u1edbi h\u01a1n v\u1edbi kh\u00f4ng gian \u0111\u1ecba ch\u1ec9 l\u1edbn h\u01a1n nhi\u1ec1u so v\u1edbi IPv4.<\/li>\n<\/ul>\n<p>M\u1ed9t t\u00ean mi\u1ec1n c\u00f3 th\u1ec3 c\u00f3 c\u1ea3 b\u1ea3n ghi A v\u00e0 AAAA \u0111\u1ec3 h\u1ed7 tr\u1ee3 k\u1ebft n\u1ed1i t\u1eeb c\u1ea3 m\u1ea1ng IPv4 v\u00e0 IPv6.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Ban-ghi-A-vs-Ban-ghi-CNAME\"><\/span>B\u1ea3n ghi A vs. B\u1ea3n ghi CNAME<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li><strong>B\u1ea3n ghi A:<\/strong> Tr\u1ecf tr\u1ef1c ti\u1ebfp m\u1ed9t t\u00ean mi\u1ec1n (ho\u1eb7c subdomain) t\u1edbi m\u1ed9t <strong>\u0111\u1ecba ch\u1ec9 IP<\/strong>.<\/li>\n<li><strong><a href=\"https:\/\/interdata.vn\/blog\/ban-ghi-cname-la-gi\/\">B\u1ea3n ghi CNAME<\/a> (Canonical Name Record):<\/strong> Tr\u1ecf m\u1ed9t t\u00ean mi\u1ec1n (ho\u1eb7c subdomain) t\u1edbi m\u1ed9t <strong>t\u00ean mi\u1ec1n kh\u00e1c<\/strong> (t\u00ean mi\u1ec1n ch\u00ednh t\u1eafc ho\u1eb7c b\u00ed danh &#8211; alias).<\/li>\n<\/ul>\n<p>V\u00ed d\u1ee5: B\u1ea1n c\u00f3 th\u1ec3 t\u1ea1o b\u1ea3n ghi CNAME cho <code>www.yourdomain.com<\/code> tr\u1ecf t\u1edbi <code>yourdomain.com<\/code>. Khi \u0111\u00f3, tr\u00ecnh duy\u1ec7t truy c\u1eadp <code>www.yourdomain.com<\/code> s\u1ebd t\u00ecm b\u1ea3n ghi A c\u1ee7a <code>yourdomain.com<\/code> \u0111\u1ec3 l\u1ea5y \u0111\u1ecba ch\u1ec9 IP. CNAME h\u1eefu \u00edch khi b\u1ea1n mu\u1ed1n nhi\u1ec1u t\u00ean c\u00f9ng tr\u1ecf v\u1ec1 m\u1ed9t n\u01a1i v\u00e0 ch\u1ec9 c\u1ea7n c\u1eadp nh\u1eadt IP t\u1ea1i m\u1ed9t b\u1ea3n ghi A g\u1ed1c. L\u01b0u \u00fd: T\u00ean mi\u1ec1n g\u1ed1c (<code>@<\/code>) th\u01b0\u1eddng kh\u00f4ng \u0111\u01b0\u1ee3c ph\u00e9p \u0111\u1eb7t b\u1ea3n ghi CNAME.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Ban-ghi-A-vs-Ban-ghi-MX\"><\/span>B\u1ea3n ghi A vs. B\u1ea3n ghi MX<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li><strong>B\u1ea3n ghi A:<\/strong> X\u00e1c \u0111\u1ecbnh \u0111\u1ecba ch\u1ec9 IP c\u1ee7a <strong>m\u00e1y ch\u1ee7 web<\/strong> ho\u1eb7c c\u00e1c d\u1ecbch v\u1ee5 kh\u00e1c li\u00ean quan \u0111\u1ebfn t\u00ean mi\u1ec1n.<\/li>\n<li><strong>B\u1ea3n ghi MX (Mail Exchanger Record):<\/strong> X\u00e1c \u0111\u1ecbnh <strong>m\u00e1y ch\u1ee7 email<\/strong> n\u00e0o ch\u1ecbu tr\u00e1ch nhi\u1ec7m nh\u1eadn th\u01b0 \u0111i\u1ec7n t\u1eed cho t\u00ean mi\u1ec1n \u0111\u00f3. Gi\u00e1 tr\u1ecb c\u1ee7a b\u1ea3n ghi MX l\u00e0 t\u00ean c\u1ee7a m\u00e1y ch\u1ee7 mail (v\u00ed d\u1ee5: <code>mail.yourdomain.com<\/code> ho\u1eb7c <code>aspmx.l.google.com<\/code>), kh\u00f4ng ph\u1ea3i \u0111\u1ecba ch\u1ec9 IP. B\u1ea3n ghi MX c\u0169ng c\u00f3 th\u00eam tr\u01b0\u1eddng \u01b0u ti\u00ean (priority).<\/li>\n<\/ul>\n<p>M\u1eb7c d\u00f9 m\u00e1y ch\u1ee7 mail \u0111\u01b0\u1ee3c ch\u1ec9 \u0111\u1ecbnh b\u1edfi b\u1ea3n ghi MX c\u0169ng c\u1ea7n c\u00f3 b\u1ea3n ghi A (ho\u1eb7c AAAA) t\u01b0\u01a1ng \u1ee9ng \u0111\u1ec3 ph\u00e2n gi\u1ea3i ra \u0111\u1ecba ch\u1ec9 IP, ch\u1ee9c n\u0103ng c\u1ee7a A v\u00e0 MX l\u00e0 ho\u00e0n to\u00e0n kh\u00e1c nhau.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cach-kiem-tra-ban-ghi-A-cua-mot-ten-mien\"><\/span>C\u00e1ch ki\u1ec3m tra b\u1ea3n ghi A c\u1ee7a m\u1ed9t t\u00ean mi\u1ec1n<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Tr\u01b0\u1edbc khi th\u1ef1c hi\u1ec7n thay \u0111\u1ed5i ho\u1eb7c \u0111\u1ec3 kh\u1eafc ph\u1ee5c s\u1ef1 c\u1ed1, b\u1ea1n th\u01b0\u1eddng c\u1ea7n ki\u1ec3m tra gi\u00e1 tr\u1ecb b\u1ea3n ghi A hi\u1ec7n t\u1ea1i c\u1ee7a m\u1ed9t t\u00ean mi\u1ec1n. C\u00f3 nhi\u1ec1u c\u00e1ch \u0111\u01a1n gi\u1ea3n \u0111\u1ec3 th\u1ef1c hi\u1ec7n vi\u1ec7c n\u00e0y:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Su-dung-cong-cu-Online\"><\/span>S\u1eed d\u1ee5ng c\u00f4ng c\u1ee5 Online<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 c\u00e1ch d\u1ec5 d\u00e0ng v\u00e0 ph\u1ed5 bi\u1ebfn nh\u1ea5t. Nhi\u1ec1u website cung c\u1ea5p d\u1ecbch v\u1ee5 tra c\u1ee9u DNS mi\u1ec5n ph\u00ed.<\/p>\n<ol>\n<li>Truy c\u1eadp m\u1ed9t <a href=\"https:\/\/interdata.vn\/blog\/page-la-gi\/\">trang web<\/a> nh\u01b0 <code>DNSChecker.org<\/code>, <code>whatsmydns.net<\/code>, ho\u1eb7c c\u00e1c c\u00f4ng c\u1ee5 ki\u1ec3m tra DNS c\u1ee7a Vi\u1ec7t Nam.<\/li>\n<li>Nh\u1eadp t\u00ean mi\u1ec1n b\u1ea1n mu\u1ed1n ki\u1ec3m tra v\u00e0o \u00f4 t\u00ecm ki\u1ebfm.<\/li>\n<li>Ch\u1ecdn lo\u1ea1i b\u1ea3n ghi l\u00e0 <code>A<\/code> t\u1eeb danh s\u00e1ch th\u1ea3 xu\u1ed1ng.<\/li>\n<li>Nh\u1ea5n n\u00fat &#8220;Search&#8221; ho\u1eb7c &#8220;Check&#8221;.<\/li>\n<li>K\u1ebft qu\u1ea3 s\u1ebd hi\u1ec3n th\u1ecb \u0111\u1ecba ch\u1ec9 IPv4 m\u00e0 t\u00ean mi\u1ec1n \u0111ang tr\u1ecf t\u1edbi t\u1eeb nhi\u1ec1u m\u00e1y ch\u1ee7 DNS tr\u00ean kh\u1eafp th\u1ebf gi\u1edbi. \u0110i\u1ec1u n\u00e0y c\u0169ng gi\u00fap ki\u1ec3m tra t\u00ecnh tr\u1ea1ng c\u1eadp nh\u1eadt DNS (propagation).<\/li>\n<\/ol>\n<p>B\u1ea1n c\u0169ng c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng c\u00f4ng c\u1ee5 <code>Dig<\/code> trong Google Admin Toolbox (<code>toolbox.googleapps.com\/apps\/dig\/<\/code>) \u0111\u1ec3 xem chi ti\u1ebft c\u00e1c b\u1ea3n ghi DNS.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Su-dung-Command-PromptTerminal-Lenh-ping-nslookup\"><\/span>S\u1eed d\u1ee5ng Command Prompt\/Terminal (L\u1ec7nh <code>ping<\/code>, <code>nslookup<\/code>)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>N\u1ebfu b\u1ea1n quen d\u00f9ng d\u00f2ng l\u1ec7nh, b\u1ea1n c\u00f3 th\u1ec3 ki\u1ec3m tra b\u1ea3n ghi A ngay tr\u00ean m\u00e1y t\u00ednh c\u1ee7a m\u00ecnh:<\/p>\n<p><strong>1. L\u1ec7nh <\/strong><code><strong>ping<\/strong><\/code><strong>:<\/strong> M\u1edf Command Prompt (Windows) ho\u1eb7c Terminal (Mac\/Linux), g\u00f5 <code>ping yourdomain.com<\/code> v\u00e0 nh\u1ea5n Enter. L\u1ec7nh <code>ping<\/code> s\u1ebd g\u1eedi y\u00eau c\u1ea7u \u0111\u1ebfn t\u00ean mi\u1ec1n v\u00e0 th\u01b0\u1eddng hi\u1ec3n th\u1ecb \u0111\u1ecba ch\u1ec9 IP m\u00e0 t\u00ean mi\u1ec1n \u0111\u00f3 ph\u00e2n gi\u1ea3i ra. \u0110\u00e2y l\u00e0 c\u00e1ch nhanh nh\u01b0ng \u0111\u00f4i khi kh\u00f4ng ho\u00e0n to\u00e0n ch\u00ednh x\u00e1c n\u1ebfu c\u00f3 c\u01a1 ch\u1ebf c\u00e2n b\u1eb1ng t\u1ea3i ho\u1eb7c <a href=\"https:\/\/interdata.vn\/blog\/tuong-lua-firewall\/\">firewall<\/a> ch\u1eb7n ping.<\/p>\n<pre><code class=\"language-plaintext\">ping example.com\r\n<\/code><\/pre>\n<p><strong>2. L\u1ec7nh <\/strong><code><strong>nslookup<\/strong><\/code><strong>:<\/strong> \u0110\u00e2y l\u00e0 c\u00f4ng c\u1ee5 chuy\u00ean d\u1ee5ng h\u01a1n \u0111\u1ec3 truy v\u1ea5n DNS. G\u00f5 <code>nslookup yourdomain.com<\/code> v\u00e0 nh\u1ea5n Enter. K\u1ebft qu\u1ea3 s\u1ebd hi\u1ec3n th\u1ecb m\u00e1y ch\u1ee7 DNS \u0111\u00e3 tr\u1ea3 l\u1eddi v\u00e0 \u0111\u1ecba ch\u1ec9 (Address) t\u01b0\u01a1ng \u1ee9ng v\u1edbi b\u1ea3n ghi A.<\/p>\n<pre><code class=\"language-plaintext\">nslookup example.com\r\n<\/code><\/pre>\n<p>B\u1ea1n c\u0169ng c\u00f3 th\u1ec3 ch\u1ec9 \u0111\u1ecbnh r\u00f5 lo\u1ea1i b\u1ea3n ghi: <code>nslookup -type=A example.com<\/code><\/p>\n<p><strong>3. L\u1ec7nh <\/strong><code><strong>dig<\/strong><\/code><strong> (th\u01b0\u1eddng c\u00f3 s\u1eb5n tr\u00ean Mac\/Linux):<\/strong> Cung c\u1ea5p th\u00f4ng tin chi ti\u1ebft h\u01a1n <code>nslookup<\/code>. G\u00f5 <code>dig yourdomain.com A +short<\/code> \u0111\u1ec3 ch\u1ec9 xem gi\u00e1 tr\u1ecb \u0111\u1ecba ch\u1ec9 IP c\u1ee7a b\u1ea3n ghi A.<\/p>\n<pre><code class=\"language-plaintext\">dig example.com A +short\r\n<\/code><\/pre>\n<p>S\u1eed d\u1ee5ng c\u00e1c ph\u01b0\u01a1ng ph\u00e1p n\u00e0y gi\u00fap b\u1ea1n x\u00e1c nh\u1eadn c\u1ea5u h\u00ecnh hi\u1ec7n t\u1ea1i ho\u1eb7c ki\u1ec3m tra xem thay \u0111\u1ed5i DNS \u0111\u00e3 \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt hay ch\u01b0a.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-03.jpg\" alt=\"B\u1ea3n ghi A 03\" width=\"750\" height=\"375\" class=\"aligncenter size-full wp-image-27839\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-03.jpg 750w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-03-300x150.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/Ban-ghi-A-03-360x180.jpg 360w\" sizes=\"auto, (max-width: 750px) 100vw, 750px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Huong-dan-co-ban-ve-Cau-hinh-Thay-doi-Ban-ghi-A\"><\/span>H\u01b0\u1edbng d\u1eabn c\u01a1 b\u1ea3n v\u1ec1 C\u1ea5u h\u00ecnh \/ Thay \u0111\u1ed5i B\u1ea3n ghi A<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Vi\u1ec7c th\u00eam, s\u1eeda ho\u1eb7c x\u00f3a b\u1ea3n ghi A th\u01b0\u1eddng \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n th\u00f4ng qua giao di\u1ec7n qu\u1ea3n l\u00fd DNS do <strong>nh\u00e0 cung c\u1ea5p t\u00ean mi\u1ec1n (Domain Registrar)<\/strong> ho\u1eb7c <strong>nh\u00e0 cung c\u1ea5p hosting<\/strong> cung c\u1ea5p. \u0110\u00f4i khi, b\u1ea1n c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng d\u1ecbch v\u1ee5 DNS c\u1ee7a b\u00ean th\u1ee9 ba nh\u01b0 <a href=\"https:\/\/interdata.vn\/blog\/cloudflare-la-gi\/\">Cloudflare<\/a>.<\/p>\n<p><strong>Quan tr\u1ecdng:<\/strong> Thay \u0111\u1ed5i c\u00e0i \u0111\u1eb7t DNS c\u00f3 th\u1ec3 \u1ea3nh h\u01b0\u1edfng tr\u1ef1c ti\u1ebfp \u0111\u1ebfn ho\u1ea1t \u0111\u1ed9ng c\u1ee7a website v\u00e0 email. H\u00e3y th\u1ef1c hi\u1ec7n c\u1ea9n th\u1eadn v\u00e0 \u0111\u1ea3m b\u1ea3o b\u1ea1n c\u00f3 th\u00f4ng tin ch\u00ednh x\u00e1c. N\u1ebfu kh\u00f4ng ch\u1eafc ch\u1eafn, h\u00e3y li\u00ean h\u1ec7 b\u1ed9 ph\u1eadn h\u1ed7 tr\u1ee3 k\u1ef9 thu\u1eadt.<\/p>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e1c b\u01b0\u1edbc t\u1ed5ng qu\u00e1t:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Xac-dinh-dia-chi-IP-dich-can-tro-den\"><\/span>X\u00e1c \u0111\u1ecbnh \u0111\u1ecba ch\u1ec9 IP \u0111\u00edch c\u1ea7n tr\u1ecf \u0111\u1ebfn<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Tr\u01b0\u1edbc ti\u00ean, b\u1ea1n c\u1ea7n bi\u1ebft ch\u00ednh x\u00e1c \u0111\u1ecba ch\u1ec9 IPv4 c\u1ee7a m\u00e1y ch\u1ee7 hosting m\u00e0 b\u1ea1n mu\u1ed1n t\u00ean mi\u1ec1n tr\u1ecf t\u1edbi. Th\u00f4ng tin n\u00e0y th\u01b0\u1eddng \u0111\u01b0\u1ee3c cung c\u1ea5p b\u1edfi nh\u00e0 cung c\u1ea5p hosting trong email ch\u00e0o m\u1eebng ho\u1eb7c trong b\u1ea3ng \u0111i\u1ec1u khi\u1ec3n t\u00e0i kho\u1ea3n hosting c\u1ee7a b\u1ea1n.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Truy-cap-khu-vuc-quan-ly-DNS\"><\/span>Truy c\u1eadp khu v\u1ef1c qu\u1ea3n l\u00fd DNS<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u0103ng nh\u1eadp v\u00e0o t\u00e0i kho\u1ea3n qu\u1ea3n tr\u1ecb n\u01a1i DNS c\u1ee7a t\u00ean mi\u1ec1n b\u1ea1n \u0111ang \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd.<\/p>\n<ul>\n<li>N\u1ebfu b\u1ea1n s\u1eed d\u1ee5ng m\u00e1y ch\u1ee7 t\u00ean mi\u1ec1n (nameserver) c\u1ee7a nh\u00e0 cung c\u1ea5p t\u00ean mi\u1ec1n, h\u00e3y \u0111\u0103ng nh\u1eadp v\u00e0o trang qu\u1ea3n tr\u1ecb t\u00ean mi\u1ec1n.<\/li>\n<li>N\u1ebfu b\u1ea1n s\u1eed d\u1ee5ng nameserver c\u1ee7a nh\u00e0 cung c\u1ea5p hosting, h\u00e3y \u0111\u0103ng nh\u1eadp v\u00e0o <a href=\"https:\/\/interdata.vn\/blog\/hosting-control-panel\/\">b\u1ea3ng \u0111i\u1ec1u khi\u1ec3n hosting<\/a> (<strong><a href=\"https:\/\/interdata.vn\/blog\/cpanel\/\">cPanel<\/a>, <a href=\"https:\/\/interdata.vn\/blog\/plesk-la-gi\/\">Plesk<\/a>, <a href=\"https:\/\/interdata.vn\/blog\/directadmin-la-gi\/\">DirectAdmin<\/a><\/strong>&#8230;).<\/li>\n<li>N\u1ebfu b\u1ea1n d\u00f9ng d\u1ecbch v\u1ee5 DNS trung gian (Cloudflare, AWS Route 53&#8230;), h\u00e3y \u0111\u0103ng nh\u1eadp v\u00e0o t\u00e0i kho\u1ea3n d\u1ecbch v\u1ee5 \u0111\u00f3.<\/li>\n<\/ul>\n<p>T\u00ecm m\u1ee5c c\u00f3 t\u00ean nh\u01b0 &#8220;Qu\u1ea3n l\u00fd DNS&#8221;, &#8220;DNS Management&#8221;, &#8220;Zone Editor&#8221;, &#8220;Advanced DNS Settings&#8221;, ho\u1eb7c t\u01b0\u01a1ng t\u1ef1.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Thao-tac-ThemSuaXoa-ban-ghi-A-Dien-thong-tin-Host-Value-TTL\"><\/span>Thao t\u00e1c Th\u00eam\/S\u1eeda\/X\u00f3a b\u1ea3n ghi A (\u0110i\u1ec1n th\u00f4ng tin Host, Value, TTL)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Trong giao di\u1ec7n qu\u1ea3n l\u00fd DNS, b\u1ea1n s\u1ebd th\u1ea5y danh s\u00e1ch c\u00e1c b\u1ea3n ghi hi\u1ec7n c\u00f3.<\/p>\n<ol>\n<li><strong>\u0110\u1ec3 th\u00eam b\u1ea3n ghi A m\u1edbi:<\/strong> T\u00ecm n\u00fat &#8220;Add Record&#8221;, &#8220;Create Record&#8221; ho\u1eb7c t\u01b0\u01a1ng t\u1ef1. Ch\u1ecdn lo\u1ea1i b\u1ea3n ghi l\u00e0 &#8220;A&#8221;. \u0110i\u1ec1n c\u00e1c tr\u01b0\u1eddng th\u00f4ng tin:\n<ul>\n<li><strong>Host\/Name:<\/strong> Nh\u1eadp <code>@<\/code> (cho t\u00ean mi\u1ec1n g\u1ed1c) ho\u1eb7c t\u00ean subdomain (v\u00ed d\u1ee5: <code>blog<\/code>).<\/li>\n<li><strong>Value\/Points to\/IP Address:<\/strong> Nh\u1eadp \u0111\u1ecba ch\u1ec9 IPv4 ch\u00ednh x\u00e1c c\u1ee7a m\u00e1y ch\u1ee7 \u0111\u00edch.<\/li>\n<li><strong>TTL:<\/strong> Ch\u1ecdn gi\u00e1 tr\u1ecb TTL mong mu\u1ed1n (th\u01b0\u1eddng c\u00f3 gi\u00e1 tr\u1ecb m\u1eb7c \u0111\u1ecbnh, v\u00ed d\u1ee5 3600).<\/li>\n<li>Nh\u1ea5n &#8220;Save&#8221; ho\u1eb7c &#8220;Add&#8221;.<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u0110\u1ec3 s\u1eeda b\u1ea3n ghi A:<\/strong> T\u00ecm b\u1ea3n ghi A b\u1ea1n mu\u1ed1n thay \u0111\u1ed5i, nh\u1ea5n v\u00e0o n\u00fat &#8220;Edit&#8221; ho\u1eb7c bi\u1ec3u t\u01b0\u1ee3ng ch\u1ec9nh s\u1eeda. Thay \u0111\u1ed5i \u0111\u1ecba ch\u1ec9 IP trong tr\u01b0\u1eddng Value ho\u1eb7c \u0111i\u1ec1u ch\u1ec9nh TTL. Nh\u1ea5n &#8220;Save&#8221;.<\/li>\n<li><strong>\u0110\u1ec3 x\u00f3a b\u1ea3n ghi A:<\/strong> T\u00ecm b\u1ea3n ghi A c\u1ea7n x\u00f3a v\u00e0 nh\u1ea5n n\u00fat &#8220;Delete&#8221; ho\u1eb7c bi\u1ec3u t\u01b0\u1ee3ng th\u00f9ng r\u00e1c. X\u00e1c nh\u1eadn vi\u1ec7c x\u00f3a (h\u00e3y c\u1ea9n th\u1eadn khi x\u00f3a).<\/li>\n<\/ol>\n<p><strong>L\u01b0u \u00fd quan tr\u1ecdng:<\/strong> Sau khi b\u1ea1n l\u01b0u thay \u0111\u1ed5i, c\u1ea7n c\u00f3 th\u1eddi gian \u0111\u1ec3 thay \u0111\u1ed5i DNS \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt tr\u00ean to\u00e0n c\u1ea7u (DNS propagation). Qu\u00e1 tr\u00ecnh n\u00e0y c\u00f3 th\u1ec3 m\u1ea5t t\u1eeb v\u00e0i ph\u00fat \u0111\u1ebfn 48 gi\u1edd, t\u00f9y thu\u1ed9c v\u00e0o c\u00e0i \u0111\u1eb7t TTL v\u00e0 c\u01a1 ch\u1ebf cache c\u1ee7a c\u00e1c m\u00e1y ch\u1ee7 DNS trung gian.<\/p>\n<p>C\u1ea5u h\u00ecnh b\u1ea3n ghi A chu\u1ea9n c\u1ea7n n\u1ec1n t\u1ea3ng hosting \u1ed5n \u0111\u1ecbnh. \u0110\u1ec3 c\u00f3 t\u1ed1c \u0111\u1ed9 cao t\u1eeb ph\u1ea7n c\u1ee9ng chuy\u00ean d\u1ee5ng (<a href=\"https:\/\/interdata.vn\/blog\/cpu-amd-epyc\/\">AMD EPYC<\/a> Gen 3th, SSD NVMe U.2), xem x\u00e9t d\u1ecbch v\u1ee5 <strong><a target=\"_blank\" rel=\"noopener noreferrer\" href=\"https:\/\/interdata.vn\/thue-hosting\/\">thu\u00ea Hosting<\/a><\/strong> uy t\u00edn t\u1ea1i InterData. Tr\u1ea3i nghi\u1ec7m ch\u1ea5t l\u01b0\u1ee3ng cao c\u1ea5p, c\u1ea5u h\u00ecnh m\u1ea1nh, <a href=\"https:\/\/interdata.vn\/blog\/bang-thong-la-gi\/\">b\u0103ng th\u00f4ng<\/a> l\u1edbn, \u1ed5n \u0111\u1ecbnh v\u1edbi dung l\u01b0\u1ee3ng t\u1ed1i \u01b0u ch\u1ec9 t\u1eeb 1K\/ng\u00e0y<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cau-hoi-thuong-gap-ve-ban-ghi-A-FAQ\"><\/span>C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 b\u1ea3n ghi A (FAQ)<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 gi\u1ea3i \u0111\u00e1p cho m\u1ed9t s\u1ed1 c\u00e2u h\u1ecfi ph\u1ed5 bi\u1ebfn m\u00e0 ng\u01b0\u1eddi d\u00f9ng th\u01b0\u1eddng g\u1eb7p khi l\u00e0m vi\u1ec7c v\u1edbi b\u1ea3n ghi A:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"TTL-cho-ban-ghi-A-nen-dat-la-bao-nhieu\"><\/span>TTL cho b\u1ea3n ghi A n\u00ean \u0111\u1eb7t l\u00e0 bao nhi\u00eau?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Kh\u00f4ng c\u00f3 c\u00e2u tr\u1ea3 l\u1eddi duy nh\u1ea5t. TTL ph\u1ed5 bi\u1ebfn l\u00e0 3600 gi\u00e2y (1 gi\u1edd).<\/p>\n<ul>\n<li><strong>TTL th\u1ea5p (v\u00ed d\u1ee5: 300 &#8211; 600 gi\u00e2y):<\/strong> Gi\u00fap thay \u0111\u1ed5i DNS c\u1eadp nh\u1eadt nhanh h\u01a1n, h\u1eefu \u00edch khi b\u1ea1n d\u1ef1 \u0111\u1ecbnh thay \u0111\u1ed5i IP s\u1eafp t\u1edbi. Tuy nhi\u00ean, vi\u1ec7c n\u00e0y t\u1ea1o nhi\u1ec1u truy v\u1ea5n h\u01a1n \u0111\u1ebfn m\u00e1y ch\u1ee7 DNS c\u1ee7a b\u1ea1n.<\/li>\n<li><strong>TTL cao (v\u00ed d\u1ee5: 14400 &#8211; 86400 gi\u00e2y):<\/strong> Gi\u1ea3m t\u1ea3i cho m\u00e1y ch\u1ee7 DNS v\u00e0 t\u0103ng t\u1ed1c \u0111\u1ed9 tra c\u1ee9u cho ng\u01b0\u1eddi d\u00f9ng cu\u1ed1i (do cache l\u00e2u h\u01a1n). Tuy nhi\u00ean, khi c\u1ea7n thay \u0111\u1ed5i IP, s\u1ebd m\u1ea5t nhi\u1ec1u th\u1eddi gian h\u01a1n \u0111\u1ec3 thay \u0111\u1ed5i \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt ho\u00e0n to\u00e0n.<\/li>\n<\/ul>\n<p>N\u1ebfu kh\u00f4ng c\u00f3 l\u00fd do \u0111\u1eb7c bi\u1ec7t, gi\u00e1 tr\u1ecb m\u1eb7c \u0111\u1ecbnh c\u1ee7a nh\u00e0 cung c\u1ea5p (th\u01b0\u1eddng l\u00e0 1 gi\u1edd ho\u1eb7c 4 gi\u1edd) l\u00e0 l\u1ef1a ch\u1ecdn an to\u00e0n.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Mot-ten-mien-co-the-co-nhieu-ban-ghi-A-khong\"><\/span>M\u1ed9t t\u00ean mi\u1ec1n c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u b\u1ea3n ghi A kh\u00f4ng?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>C\u00f3. M\u1ed9t t\u00ean mi\u1ec1n ho\u1eb7c t\u00ean mi\u1ec1n ph\u1ee5 c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u b\u1ea3n ghi A tr\u1ecf \u0111\u1ebfn c\u00e1c \u0111\u1ecba ch\u1ec9 IP kh\u00e1c nhau. K\u1ef9 thu\u1eadt n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 <strong>DNS Round Robin<\/strong>.<\/p>\n<p>Khi m\u00e1y ch\u1ee7 DNS nh\u1eadn truy v\u1ea5n, m\u00e1y ch\u1ee7 s\u1ebd tr\u1ea3 v\u1ec1 danh s\u00e1ch c\u00e1c \u0111\u1ecba ch\u1ec9 IP \u0111\u00f3, th\u01b0\u1eddng theo th\u1ee9 t\u1ef1 xoay v\u00f2ng. Tr\u00ecnh duy\u1ec7t c\u1ee7a ng\u01b0\u1eddi d\u00f9ng s\u1ebd th\u1eed k\u1ebft n\u1ed1i \u0111\u1ebfn m\u1ed9t trong c\u00e1c IP \u0111\u00f3. \u0110\u00e2y l\u00e0 m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n \u0111\u1ec3 th\u1ef1c hi\u1ec7n <strong>c\u00e2n b\u1eb1ng t\u1ea3i (<a href=\"https:\/\/interdata.vn\/blog\/load-balancing\/\">load balancing<\/a>)<\/strong> ho\u1eb7c <strong>d\u1ef1 ph\u00f2ng c\u01a1 b\u1ea3n (<a href=\"https:\/\/interdata.vn\/blog\/failover-la-gi\/\">failover<\/a>)<\/strong> gi\u1eefa nhi\u1ec1u m\u00e1y ch\u1ee7 web.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Mat-bao-lau-de-thay-doi-ban-ghi-A-co-hieu-luc-DNS-Propagation\"><\/span>M\u1ea5t bao l\u00e2u \u0111\u1ec3 thay \u0111\u1ed5i b\u1ea3n ghi A c\u00f3 hi\u1ec7u l\u1ef1c? (DNS Propagation)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Th\u1eddi gian \u0111\u1ec3 thay \u0111\u1ed5i b\u1ea3n ghi A \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt tr\u00ean to\u00e0n b\u1ed9 Internet (DNS Propagation) ph\u1ee5 thu\u1ed9c ch\u1ee7 y\u1ebfu v\u00e0o c\u00e0i \u0111\u1eb7t <strong>TTL<\/strong> c\u1ee7a b\u1ea3n ghi <i>tr\u01b0\u1edbc khi<\/i> b\u1ea1n thay \u0111\u1ed5i v\u00e0 c\u01a1 ch\u1ebf cache c\u1ee7a c\u00e1c m\u00e1y ch\u1ee7 DNS trung gian tr\u00ean to\u00e0n c\u1ea7u.<\/p>\n<p>Th\u00f4ng th\u01b0\u1eddng, qu\u00e1 tr\u00ecnh n\u00e0y c\u00f3 th\u1ec3 m\u1ea5t t\u1eeb v\u00e0i ph\u00fat \u0111\u1ebfn t\u1ed1i \u0111a 48 gi\u1edd, \u0111\u00f4i khi l\u00e2u h\u01a1n trong tr\u01b0\u1eddng h\u1ee3p hi\u1ebfm. B\u1ea1n c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng c\u00e1c c\u00f4ng c\u1ee5 DNS Checker tr\u1ef1c tuy\u1ebfn \u0111\u1ec3 theo d\u00f5i ti\u1ebfn tr\u00ecnh c\u1eadp nh\u1eadt t\u1eeb c\u00e1c \u0111\u1ecba \u0111i\u1ec3m kh\u00e1c nhau. Gi\u1ea3m TTL tr\u01b0\u1edbc khi th\u1ef1c hi\u1ec7n thay \u0111\u1ed5i c\u00f3 th\u1ec3 gi\u00fap r\u00fat ng\u1eafn th\u1eddi gian ch\u1edd \u0111\u1ee3i.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Su-khac-nhau-chinh-giua-ban-ghi-A-va-AAAA-la-gi\"><\/span>S\u1ef1 kh\u00e1c nhau ch\u00ednh gi\u1eefa b\u1ea3n ghi A v\u00e0 AAAA l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>S\u1ef1 kh\u00e1c bi\u1ec7t c\u1ed1t l\u00f5i n\u1eb1m \u1edf phi\u00ean b\u1ea3n \u0111\u1ecba ch\u1ec9 IP m\u00e0 ch\u00fang \u00e1nh x\u1ea1 t\u1edbi:<\/p>\n<ul>\n<li><strong>B\u1ea3n ghi A:<\/strong> D\u00f9ng cho \u0111\u1ecba ch\u1ec9 <strong>IPv4<\/strong>.<\/li>\n<li><strong>B\u1ea3n ghi AAAA:<\/strong> D\u00f9ng cho \u0111\u1ecba ch\u1ec9 <strong>IPv6<\/strong>.<\/li>\n<\/ul>\n<p>C\u1ea3 hai \u0111\u1ec1u c\u00f9ng m\u1ee5c \u0111\u00edch l\u00e0 li\u00ean k\u1ebft t\u00ean mi\u1ec1n v\u1edbi \u0111\u1ecba ch\u1ec9 IP, nh\u01b0ng d\u00e0nh cho hai phi\u00ean b\u1ea3n giao th\u1ee9c Internet kh\u00e1c nhau.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>B\u1ea3n ghi A (A Record) l\u00e0 th\u00e0nh ph\u1ea7n n\u1ec1n t\u1ea3ng gi\u00fap Internet ho\u1ea1t \u0111\u1ed9ng nh\u01b0 ch\u00fang ta bi\u1ebft. N\u1ebfu kh\u00f4ng c\u00f3 b\u1ea3n ghi n\u00e0y, vi\u1ec7c truy c\u1eadp website b\u1eb1ng t\u00ean mi\u1ec1n d\u1ec5 nh\u1edb nh\u01b0 google.com l\u00e0 kh\u00f4ng th\u1ec3. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd gi\u1ea3i th\u00edch chi ti\u1ebft b\u1ea3n ghi A l\u00e0 g\u00ec, c\u00e1ch ho\u1ea1t \u0111\u1ed9ng, t\u1ea7m<\/p>\n","protected":false},"author":2,"featured_media":27840,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[149],"tags":[],"class_list":["post-27837","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-control-panel"],"_links":{"self":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/27837","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/comments?post=27837"}],"version-history":[{"count":1,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/27837\/revisions"}],"predecessor-version":[{"id":27843,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/27837\/revisions\/27843"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media\/27840"}],"wp:attachment":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media?parent=27837"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/categories?post=27837"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/tags?post=27837"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}