{"id":37912,"date":"2026-01-12T16:02:26","date_gmt":"2026-01-12T09:02:26","guid":{"rendered":"https:\/\/interdata.vn\/blog\/?p=37912"},"modified":"2026-01-28T10:15:38","modified_gmt":"2026-01-28T03:15:38","slug":"dkim-la-gi","status":"publish","type":"post","link":"https:\/\/interdata.vn\/blog\/dkim-la-gi\/","title":{"rendered":"DKIM l\u00e0 g\u00ec? Vai tr\u00f2, l\u1ee3i \u00edch &#038; c\u00e1ch c\u1ea5u h\u00ecnh DKIM chi ti\u1ebft nh\u1ea5t"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 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\/dkim-la-gi\/#DKIM-la-gi\" >DKIM 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\/dkim-la-gi\/#Tai-sao-DKIM-quan-trong-voi-doanh-nghiep\" >T\u1ea1i sao DKIM quan tr\u1ecdng v\u1edbi doanh nghi\u1ec7p?<\/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\/dkim-la-gi\/#Tang-ty-le-Email-vao-Inbox-Deliverability\" >T\u0103ng t\u1ef7 l\u1ec7 Email v\u00e0o Inbox (Deliverability)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#Bao-ve-uy-tin-thuong-hieu-va-chong-gia-mao-Spoofing\" >B\u1ea3o v\u1ec7 uy t\u00edn th\u01b0\u01a1ng hi\u1ec7u v\u00e0 ch\u1ed1ng gi\u1ea3 m\u1ea1o (Spoofing)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#Dieu-kien-can-cho-DMARC\" >\u0110i\u1ec1u ki\u1ec7n c\u1ea7n cho DMARC<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#DKIM-hoat-dong-nhu-the-nao-trong-he-thong-email\" >DKIM ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o trong h\u1ec7 th\u1ed1ng email?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#Phan-biet-SPF-DKIM-va-DMARC\" >Ph\u00e2n bi\u1ec7t SPF, DKIM v\u00e0 DMARC<\/a><\/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\/dkim-la-gi\/#Khi-nao-can-cau-hinh-DKIM\" >Khi n\u00e0o c\u1ea7n c\u1ea5u h\u00ecnh DKIM?<\/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\/dkim-la-gi\/#1-Doanh-nghiep-su-dung-Email-theo-ten-mien-rieng\" >1. Doanh nghi\u1ec7p s\u1eed d\u1ee5ng Email theo t\u00ean mi\u1ec1n ri\u00eang<\/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\/dkim-la-gi\/#2-Trien-khai-cac-chien-dich-Email-Marketing\" >2. Tri\u1ec3n khai c\u00e1c chi\u1ebfn d\u1ecbch Email Marketing<\/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\/dkim-la-gi\/#3-Website-gui-email-tu-dong-Transactional-Email\" >3. Website g\u1eedi email t\u1ef1 \u0111\u1ed9ng (Transactional Email)<\/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\/dkim-la-gi\/#4-Khi-nhan-thay-ty-le-mo-email-Open-Rate-giam-dot-ngot\" >4. Khi nh\u1eadn th\u1ea5y t\u1ef7 l\u1ec7 m\u1edf email (Open Rate) gi\u1ea3m \u0111\u1ed9t ng\u1ed9t<\/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\/dkim-la-gi\/#Cau-hinh-DKIM-cho-he-thong-mail-server\" >C\u1ea5u h\u00ecnh DKIM cho h\u1ec7 th\u1ed1ng mail server<\/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\/dkim-la-gi\/#Cach-xac-minh-DKIM-o-phia-nguoi-nhan\" >C\u00e1ch x\u00e1c minh DKIM \u1edf ph\u00eda ng\u01b0\u1eddi nh\u1eadn<\/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\/dkim-la-gi\/#Cach-thiet-lap-DKIM-o-phia-nguoi-gui\" >C\u00e1ch thi\u1ebft l\u1eadp DKIM \u1edf ph\u00eda ng\u01b0\u1eddi g\u1eedi<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#Huong-dan-cai-dat-DKIM-tren-Microsoft-365-Defender\" >H\u01b0\u1edbng d\u1eabn c\u00e0i \u0111\u1eb7t DKIM tr\u00ean Microsoft 365 Defender<\/a><\/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\/dkim-la-gi\/#Cac-loi-thuong-gap-khi-cai-dat-DKIM\" >C\u00e1c l\u1ed7i th\u01b0\u1eddng g\u1eb7p khi c\u00e0i \u0111\u1eb7t DKIM<\/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\/dkim-la-gi\/#1-Copy-thieu-hoac-sai-ky-tu-trong-chuoi-ma-hoa\" >1. Copy thi\u1ebfu ho\u1eb7c sai k\u00fd t\u1ef1 trong chu\u1ed7i m\u00e3 h\u00f3a<\/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\/dkim-la-gi\/#2-DNS-chua-cap-nhat-Propagation-Delay\" >2. DNS ch\u01b0a c\u1eadp nh\u1eadt (Propagation Delay)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-20\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#3-Sai-Selector-Bo-dinh-danh\" >3. Sai Selector (B\u1ed9 \u0111\u1ecbnh danh)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-21\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#4-Do-dai-khoa-vuot-qua-gioi-han-cua-nha-cung-cap-DNS\" >4. \u0110\u1ed9 d\u00e0i kh\u00f3a v\u01b0\u1ee3t qu\u00e1 gi\u1edbi h\u1ea1n c\u1ee7a nh\u00e0 cung c\u1ea5p DNS<\/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\/dkim-la-gi\/#5-Xung-dot-nhieu-ban-ghi-DKIM\" >5. Xung \u0111\u1ed9t nhi\u1ec1u b\u1ea3n ghi DKIM<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-23\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#Cau-hoi-thuong-gap-ve-DKIM-FAQ\" >C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 DKIM (FAQ)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-24\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#Khong-co-DKIM-email-co-gui-duoc-khong\" >Kh\u00f4ng c\u00f3 DKIM email c\u00f3 g\u1eedi \u0111\u01b0\u1ee3c kh\u00f4ng?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-25\" href=\"https:\/\/interdata.vn\/blog\/dkim-la-gi\/#DKIM-co-thay-the-duoc-SPF-khong\" >DKIM c\u00f3 thay th\u1ebf \u0111\u01b0\u1ee3c SPF kh\u00f4ng?<\/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\/dkim-la-gi\/#DKIM-co-giup-email-vao-Inbox-100-khong\" >DKIM c\u00f3 gi\u00fap email v\u00e0o Inbox 100% 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\/dkim-la-gi\/#Toi-co-can-thay-doi-ma-DKIM-dinh-ky-khong-Key-Rotation\" >T\u00f4i c\u00f3 c\u1ea7n thay \u0111\u1ed5i m\u00e3 DKIM \u0111\u1ecbnh k\u1ef3 kh\u00f4ng (Key Rotation)?<\/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\/dkim-la-gi\/#Ket-luan\" >K\u1ebft lu\u1eadn<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<p>B\u1ea1n g\u1eedi email b\u00e1o gi\u00e1 cho \u0111\u1ed1i t\u00e1c nh\u01b0ng h\u1ecd ph\u1ea3n h\u1ed3i r\u1eb1ng ch\u01b0a nh\u1eadn \u0111\u01b0\u1ee3c, ho\u1eb7c t\u1ec7 h\u01a1n l\u00e0 email n\u1eb1m trong h\u00f2m th\u01b0 Spam? T\u1ea1i InterData, ch\u00fang t\u00f4i hi\u1ec3u r\u1eb1ng vi\u1ec7c email b\u1ecb \u0111\u00e1nh d\u1ea5u l\u00e0 kh\u00f4ng an to\u00e0n \u1ea3nh h\u01b0\u1edfng nghi\u00eam tr\u1ecdng \u0111\u1ebfn uy t\u00edn doanh nghi\u1ec7p. Gi\u1ea3i ph\u00e1p c\u1ed1t l\u00f5i cho v\u1ea5n \u0111\u1ec1 n\u00e0y ch\u00ednh l\u00e0 DKIM. V\u1eady <strong>DKIM l\u00e0 g\u00ec<\/strong>, ho\u1ea1t \u0111\u1ed9ng ra sao v\u00e0 v\u00ec sao \u0111\u00e2y l\u00e0 c\u1ea5u h\u00ecnh kh\u00f4ng th\u1ec3 thi\u1ebfu \u0111\u1ed1i v\u1edbi email doanh nghi\u1ec7p? N\u1ed9i dung d\u01b0\u1edbi \u0111\u00e2y s\u1ebd gi\u00fap b\u1ea1n hi\u1ec3u r\u00f5 t\u1eeb n\u1ec1n t\u1ea3ng \u0111\u1ebfn c\u00e1ch \u1ee9ng d\u1ee5ng DKIM m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"DKIM-la-gi\"><\/span>DKIM l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>DKIM l\u00e0 vi\u1ebft t\u1eaft c\u1ee7a <strong>DomainKeys Identified Mail<\/strong>\u00a0l\u00e0 m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c x\u00e1c th\u1ef1c email cho ph\u00e9p ng\u01b0\u1eddi nh\u1eadn ki\u1ec3m tra xem m\u1ed9t email c\u00f3 th\u1ef1c s\u1ef1 \u0111\u01b0\u1ee3c g\u1eedi t\u1eeb ch\u1ee7 s\u1edf h\u1eefu c\u1ee7a t\u00ean mi\u1ec1n \u0111\u00f3 hay kh\u00f4ng.<\/p>\n<p>N\u00f3i m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n, ti\u00eau chu\u1ea9n b\u1ea3o m\u1eadt email DKIM cung c\u1ea5p m\u1ed9t ch\u1eef k\u00fd s\u1ed1 (digital signature) \u0111\u01b0\u1ee3c g\u1eafn v\u00e0o ti\u00eau \u0111\u1ec1 (header) c\u1ee7a m\u1ed7i email g\u1eedi \u0111i. Ch\u1eef k\u00fd n\u00e0y v\u00f4 h\u00ecnh v\u1edbi ng\u01b0\u1eddi \u0111\u1ecdc th\u00f4ng th\u01b0\u1eddng nh\u01b0ng l\u1ea1i c\u1ef1c k\u1ef3 quan tr\u1ecdng \u0111\u1ed1i v\u1edbi c\u00e1c m\u00e1y ch\u1ee7 nh\u1eadn th\u01b0 (Mail Server). H\u1ec7 th\u1ed1ng nh\u1eadn s\u1ebd s\u1eed d\u1ee5ng ch\u1eef k\u00fd n\u00e0y \u0111\u1ec3 x\u00e1c minh hai y\u1ebfu t\u1ed1:<\/p>\n<ol>\n<li>Email th\u1ef1c s\u1ef1 xu\u1ea5t ph\u00e1t t\u1eeb t\u00ean mi\u1ec1n \u0111\u00e3 \u0111\u0103ng k\u00fd.<\/li>\n<li>N\u1ed9i dung email kh\u00f4ng b\u1ecb s\u1eeda \u0111\u1ed5i trong qu\u00e1 tr\u00ecnh truy\u1ec1n t\u1ea3i tr\u00ean internet.<\/li>\n<\/ol>\n<figure id=\"attachment_37914\" aria-describedby=\"caption-attachment-37914\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-37914\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/DKIM-la-gi.jpg\" alt=\"DKIM l\u00e0 g\u00ec\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/DKIM-la-gi.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/DKIM-la-gi-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/DKIM-la-gi-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-37914\" class=\"wp-caption-text\">DKIM l\u00e0 g\u00ec?<\/figcaption><\/figure>\n<p>DKIM kh\u00f4ng t\u1ef1 nhi\u00ean xu\u1ea5t hi\u1ec7n m\u00e0 l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a s\u1ef1 h\u1ee3p nh\u1ea5t gi\u1eefa hai c\u00f4ng ngh\u1ec7 b\u1ea3o m\u1eadt ti\u00ean ti\u1ebfn v\u00e0o \u0111\u1ea7u nh\u1eefng n\u0103m 2000:<\/p>\n<ul>\n<li><strong>DomainKeys:<\/strong> \u0110\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi Yahoo nh\u1eb1m x\u00e1c minh t\u00ean mi\u1ec1n g\u1eedi th\u01b0.<\/li>\n<li><strong>Identified Internet Mail:<\/strong> \u0110\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi Cisco nh\u1eb1m x\u00e1c th\u1ef1c danh t\u00ednh.<\/li>\n<\/ul>\n<p>N\u0103m 2004, Yahoo v\u00e0 Cisco \u0111\u00e3 k\u1ebft h\u1ee3p hai ti\u00eau chu\u1ea9n n\u00e0y \u0111\u1ec3 t\u1ea1o ra DKIM. \u0110\u1ebfn n\u0103m 2007, IETF (Internet Engineering Task Force) ch\u00ednh th\u1ee9c c\u00f4ng nh\u1eadn DKIM l\u00e0 m\u1ed9t ti\u00eau chu\u1ea9n k\u1ef9 thu\u1eadt. \u0110i\u1ec1u n\u00e0y cho th\u1ea5y t\u00ednh \u1ed5n \u0111\u1ecbnh v\u00e0 t\u1ea7m quan tr\u1ecdng c\u1ee7a c\u00f4ng ngh\u1ec7 n\u00e0y trong h\u1ea1 t\u1ea7ng email to\u00e0n c\u1ea7u.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tai-sao-DKIM-quan-trong-voi-doanh-nghiep\"><\/span>T\u1ea1i sao DKIM quan tr\u1ecdng v\u1edbi doanh nghi\u1ec7p?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Nhi\u1ec1u ng\u01b0\u1eddi d\u00f9ng th\u01b0\u1eddng b\u1ecf qua b\u01b0\u1edbc c\u1ea5u h\u00ecnh DKIM v\u00ec cho r\u1eb1ng ch\u1ec9 c\u1ea7n SPF l\u00e0 \u0111\u1ee7, ho\u1eb7c ngh\u0129 r\u1eb1ng email hosting \u0111\u00e3 &#8220;t\u1ef1 lo&#8221; vi\u1ec7c n\u00e0y. Tuy nhi\u00ean, theo kinh nghi\u1ec7m tri\u1ec3n khai d\u1ecbch v\u1ee5 t\u1ea1i InterData, vi\u1ec7c thi\u1ebfu DKIM l\u00e0 nguy\u00ean nh\u00e2n h\u00e0ng \u0111\u1ea7u khi\u1ebfn c\u00e1c chi\u1ebfn d\u1ecbch Email Marketing th\u1ea5t b\u1ea1i.<\/p>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 nh\u1eefng l\u00fd do c\u1ee5 th\u1ec3 gi\u1ea3i th\u00edch t\u1ea1i sao doanh nghi\u1ec7p b\u1eaft bu\u1ed9c ph\u1ea3i quan t\u00e2m \u0111\u1ebfn DKIM.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Tang-ty-le-Email-vao-Inbox-Deliverability\"><\/span>T\u0103ng t\u1ef7 l\u1ec7 Email v\u00e0o Inbox (Deliverability)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>C\u00e1c nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 email l\u1edbn (ISP) nh\u01b0 Gmail, Yahoo, Microsoft xem x\u00e9t r\u1ea5t k\u1ef9 \u0111\u1ed9 uy t\u00edn c\u1ee7a t\u00ean mi\u1ec1n g\u1eedi \u0111\u1ebfn.\u00a0ISP s\u1eed d\u1ee5ng t\u00edn hi\u1ec7u x\u00e1c th\u1ef1c DKIM nh\u01b0 m\u1ed9t y\u1ebfu t\u1ed1 \u0111\u00e1nh gi\u00e1 \u0111\u1ed9 tin c\u1eady<\/p>\n<p>Khi email c\u1ee7a b\u1ea1n mang theo ch\u1eef k\u00fd DKIM h\u1ee3p l\u1ec7, b\u1ed9 l\u1ecdc spam s\u1ebd hi\u1ec3u r\u1eb1ng: &#8220;Email n\u00e0y \u0111\u1ebfn t\u1eeb ngu\u1ed3n ch\u00ednh ch\u1ee7 v\u00e0 ch\u1ecbu tr\u00e1ch nhi\u1ec7m cho n\u1ed9i dung b\u00ean trong&#8221;. Nh\u1edd \u0111\u00f3, x\u00e1c su\u1ea5t email \u0111i th\u1eb3ng v\u00e0o h\u1ed9p th\u01b0 \u0111\u1ebfn (Inbox) thay v\u00ec m\u1ee5c Spam hay Promotion s\u1ebd t\u0103ng l\u00ean \u0111\u00e1ng k\u1ec3. \u0110\u1ed1i v\u1edbi c\u00e1c doanh nghi\u1ec7p th\u1ef1c hi\u1ec7n Cold Email hay g\u1eedi b\u1ea3n tin (Newsletter), \u0111\u00e2y l\u00e0 y\u1ebfu t\u1ed1 s\u1ed1ng c\u00f2n.<\/p>\n<figure id=\"attachment_37915\" aria-describedby=\"caption-attachment-37915\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-37915\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Tai-sao-DKIM-quan-trong-voi-doanh-nghiep.jpg\" alt=\"T\u1ea1i sao DKIM quan tr\u1ecdng v\u1edbi doanh nghi\u1ec7p\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Tai-sao-DKIM-quan-trong-voi-doanh-nghiep.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Tai-sao-DKIM-quan-trong-voi-doanh-nghiep-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Tai-sao-DKIM-quan-trong-voi-doanh-nghiep-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-37915\" class=\"wp-caption-text\">T\u1ea1i sao DKIM quan tr\u1ecdng v\u1edbi doanh nghi\u1ec7p?<\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"Bao-ve-uy-tin-thuong-hieu-va-chong-gia-mao-Spoofing\"><\/span>B\u1ea3o v\u1ec7 uy t\u00edn th\u01b0\u01a1ng hi\u1ec7u v\u00e0 ch\u1ed1ng gi\u1ea3 m\u1ea1o (Spoofing)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>K\u1ebb x\u1ea5u th\u01b0\u1eddng s\u1eed d\u1ee5ng k\u1ef9 thu\u1eadt Spoofing \u0111\u1ec3 g\u1eedi email l\u1eeba \u0111\u1ea3o d\u01b0\u1edbi danh ngh\u0129a c\u1ee7a c\u00e1c t\u1ed5 ch\u1ee9c uy t\u00edn (v\u00ed d\u1ee5: ng\u00e2n h\u00e0ng, c\u00f4ng ty t\u00e0i ch\u00ednh, ho\u1eb7c ch\u00ednh \u0111\u1ed1i t\u00e1c c\u1ee7a b\u1ea1n). N\u1ebfu kh\u00f4ng c\u00f3 ti\u00eau chu\u1ea9n b\u1ea3o m\u1eadt email DKIM, k\u1ebb t\u1ea5n c\u00f4ng c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng thay \u0111\u1ed5i n\u1ed9i dung email tr\u00ean \u0111\u01b0\u1eddng truy\u1ec1n ho\u1eb7c gi\u1ea3 m\u1ea1o \u0111\u1ecba ch\u1ec9 ng\u01b0\u1eddi g\u1eedi m\u00e0 kh\u00f4ng \u0111\u1ec3 l\u1ea1i d\u1ea5u v\u1ebft.<\/p>\n<p>X\u00e1c th\u1ef1c DKIM gi\u00fap b\u1ea3o v\u1ec7 to\u00e0n v\u1eb9n n\u1ed9i dung. Ch\u1ec9 c\u1ea7n m\u1ed9t k\u00fd t\u1ef1 trong ti\u00eau \u0111\u1ec1 ho\u1eb7c th\u00e2n b\u00e0i email b\u1ecb thay \u0111\u1ed5i, ch\u1eef k\u00fd DKIM s\u1ebd m\u1ea5t hi\u1ec7u l\u1ef1c ngay l\u1eadp t\u1ee9c. \u0110i\u1ec1u n\u00e0y gi\u00fap ng\u0103n ch\u1eb7n c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng trung gian (Man-in-the-middle attacks), ph\u00e1t hi\u1ec7n vi\u1ec7c n\u1ed9i dung b\u1ecb thay \u0111\u1ed5i, kh\u00f4ng m\u00e3 h\u00f3a n\u1ed9i dung v\u00e0 b\u1ea3o v\u1ec7 h\u00ecnh \u1ea3nh th\u01b0\u01a1ng hi\u1ec7u c\u1ee7a b\u1ea1n trong m\u1eaft kh\u00e1ch h\u00e0ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Dieu-kien-can-cho-DMARC\"><\/span>\u0110i\u1ec1u ki\u1ec7n c\u1ea7n cho DMARC<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>R\u1ea5t nhi\u1ec1u doanh nghi\u1ec7p mu\u1ed1n tri\u1ec3n khai DMARC \u0111\u1ec3 nh\u1eadn b\u00e1o c\u00e1o v\u1ec1 t\u00ecnh h\u00ecnh g\u1eedi mail ho\u1eb7c ra l\u1ec7nh ch\u1eb7n ho\u00e0n to\u00e0n email gi\u1ea3 m\u1ea1o. Tuy nhi\u00ean, DMARC kh\u00f4ng th\u1ec3 ho\u1ea1t \u0111\u1ed9ng \u0111\u1ed9c l\u1eadp. DMARC d\u1ef1a tr\u00ean k\u1ebft qu\u1ea3 x\u00e1c th\u1ef1c c\u1ee7a SPF v\u00e0 DKIM.<\/p>\n<p>N\u1ebfu b\u1ea1n ch\u01b0a c\u1ea5u h\u00ecnh DKIM ho\u1eb7c c\u1ea5u h\u00ecnh sai, vi\u1ec7c tri\u1ec3n khai DMARC s\u1ebd d\u1eabn \u0111\u1ebfn h\u1eadu qu\u1ea3 l\u00e0 ch\u00ednh email th\u1eadt c\u1ee7a b\u1ea1n c\u0169ng b\u1ecb ch\u1eb7n. Do \u0111\u00f3, hi\u1ec3u r\u00f5 <strong>DKIM<\/strong>\u00a0v\u00e0 c\u00e0i \u0111\u1eb7t \u0111\u00fang l\u00e0 b\u01b0\u1edbc \u0111\u1ec7m b\u1eaft bu\u1ed9c \u0111\u1ec3 ti\u1ebfn t\u1edbi m\u1ee9c \u0111\u1ed9 b\u1ea3o m\u1eadt cao nh\u1ea5t cho h\u1ec7 th\u1ed1ng th\u01b0 \u0111i\u1ec7n t\u1eed.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"DKIM-hoat-dong-nhu-the-nao-trong-he-thong-email\"><\/span>DKIM ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o trong h\u1ec7 th\u1ed1ng email?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>V\u1ec1 b\u1ea3n ch\u1ea5t, <strong>DKIM l\u00e0 m\u1ed9t c\u01a1 ch\u1ebf x\u00e1c th\u1ef1c email<\/strong>, kh\u00f4ng ph\u1ea3i c\u00f4ng c\u1ee5 tr\u1ef1c ti\u1ebfp \u0111\u1ec3 l\u1ecdc hay ch\u1eb7n spam. Tuy nhi\u00ean, do DKIM gi\u00fap ph\u00e1t hi\u1ec7n th\u01b0 gi\u1ea3 m\u1ea1o, l\u1eeba \u0111\u1ea3o ho\u1eb7c email c\u00f3 nguy c\u01a1 ch\u1ee9a m\u00e3 \u0111\u1ed9c, n\u00ean nhi\u1ec1u ng\u01b0\u1eddi th\u01b0\u1eddng hi\u1ec3u nh\u1ea7m r\u1eb1ng DKIM \u0111\u01b0\u1ee3c t\u1ea1o ra \u0111\u1ec3 ch\u1ed1ng spam.<\/p>\n<p>C\u01a1 ch\u1ebf DKIM \u0111\u01b0\u1ee3c tri\u1ec3n khai th\u00f4ng qua <strong>hai th\u00e0nh ph\u1ea7n t\u00e1ch bi\u1ec7t: k\u00fd v\u00e0 x\u00e1c minh<\/strong>. M\u1ed7i ph\u1ea7n c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c x\u1eed l\u00fd b\u1edfi c\u00e1c module kh\u00e1c nhau trong <strong>Mail Transfer Agent (MTA)<\/strong> c\u1ee7a h\u1ec7 th\u1ed1ng g\u1eedi v\u00e0 nh\u1eadn email.<\/p>\n<p>T\u00f9y v\u00e0o t\u1eebng n\u1ec1n t\u1ea3ng mail server, quy tr\u00ecnh c\u1ea5u h\u00ecnh DKIM c\u00f3 th\u1ec3 kh\u00e1c nhau. Tuy v\u1eady, v\u1ec1 m\u1eb7t nguy\u00ean l\u00fd, DKIM th\u01b0\u1eddng \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp theo c\u00e1c b\u01b0\u1edbc chu\u1ea9n d\u01b0\u1edbi \u0111\u00e2y.<\/p>\n<p>Quy tr\u00ecnh DKIM \u1edf ph\u00eda g\u1eedi email:<\/p>\n<ul>\n<li><strong>B\u01b0\u1edbc 1:<\/strong> H\u1ec7 th\u1ed1ng mail server t\u1ea1o m\u1ed9t c\u1eb7p kh\u00f3a g\u1ed3m <strong>Private Key v\u00e0 Public Key<\/strong>, th\u01b0\u1eddng \u0111\u01b0\u1ee3c sinh b\u1eb1ng c\u00e1c c\u00f4ng c\u1ee5 nh\u01b0 OpenSSL.<\/li>\n<li><strong>B\u01b0\u1edbc 2:<\/strong> Kh\u00f3a <strong>Public Key<\/strong> \u0111\u01b0\u1ee3c khai b\u00e1o d\u01b0\u1edbi d\u1ea1ng <strong>b\u1ea3n ghi TXT tr\u00ean DNS<\/strong>, g\u1eafn v\u1edbi t\u00ean mi\u1ec1n d\u00f9ng \u0111\u1ec3 g\u1eedi email.<\/li>\n<li><strong>B\u01b0\u1edbc 3:<\/strong> Mail server \u0111\u01b0\u1ee3c c\u1ea5u h\u00ecnh s\u1eed d\u1ee5ng <strong>Private Key<\/strong> \u0111\u1ec3 k\u00fd s\u1ed1 v\u00e0o email tr\u01b0\u1edbc khi g\u1eedi \u0111i. Kh\u00f3a ri\u00eang n\u00e0y ch\u1ec9 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef tr\u00ean mail server, do \u0111\u00f3 kh\u00f4ng th\u1ec3 b\u1ecb gi\u1ea3 m\u1ea1o t\u1eeb b\u00ean ngo\u00e0i.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Phan-biet-SPF-DKIM-va-DMARC\"><\/span>Ph\u00e2n bi\u1ec7t SPF, DKIM v\u00e0 DMARC<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Trong th\u1ebf gi\u1edbi b\u1ea3o m\u1eadt email, SPF, DKIM v\u00e0 DMARC th\u01b0\u1eddng \u0111\u01b0\u1ee3c nh\u1eafc \u0111\u1ebfn nh\u01b0 m\u1ed9t b\u1ed9 ba kh\u00f4ng th\u1ec3 t\u00e1ch r\u1eddi. Tuy nhi\u00ean, m\u1ed7i giao th\u1ee9c \u0111\u00f3ng m\u1ed9t vai tr\u00f2 v\u00e0 nhi\u1ec7m v\u1ee5 ho\u00e0n to\u00e0n kh\u00e1c nhau. Vi\u1ec7c nh\u1ea7m l\u1eabn gi\u1eefa ch\u1ee9c n\u0103ng c\u1ee7a ch\u00fang d\u1eabn \u0111\u1ebfn c\u1ea5u h\u00ecnh sai s\u00f3t.<\/p>\n<figure id=\"attachment_37920\" aria-describedby=\"caption-attachment-37920\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-37920\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Phan-biet-SPF-DKIM-va-DMARC.jpg\" alt=\"Ph\u00e2n bi\u1ec7t SPF, DKIM v\u00e0 DMARC\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Phan-biet-SPF-DKIM-va-DMARC.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Phan-biet-SPF-DKIM-va-DMARC-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Phan-biet-SPF-DKIM-va-DMARC-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-37920\" class=\"wp-caption-text\">Ph\u00e2n bi\u1ec7t SPF, DKIM v\u00e0 DMARC<\/figcaption><\/figure>\n<p>InterData \u0111\u00e3 t\u1ed5ng h\u1ee3p b\u1ea3ng so s\u00e1nh d\u01b0\u1edbi \u0111\u00e2y \u0111\u1ec3 b\u1ea1n d\u1ec5 d\u00e0ng h\u00ecnh dung:<\/p>\n<div style=\"overflow-x: auto; margin: 24px 0;\">\n<table style=\"width: 100%; border-collapse: collapse; font-family: Arial, Helvetica, sans-serif; font-size: 15px; line-height: 1.6;\">\n<thead>\n<tr>\n<th style=\"background: linear-gradient(135deg,#0C40F4,#077FFA); color: #ffffff; padding: 14px; border: 1px solid #e6e9f5; text-align: left;\">\u0110\u1eb7c \u0111i\u1ec3m<\/th>\n<th style=\"background: linear-gradient(135deg,#077FFA,#0497FC); color: #ffffff; padding: 14px; border: 1px solid #e6e9f5; text-align: left;\">SPF (Sender Policy Framework)<\/th>\n<th style=\"background: linear-gradient(135deg,#0497FC,#077FFA); color: #ffffff; padding: 14px; border: 1px solid #e6e9f5; text-align: left;\">DKIM (DomainKeys Identified Mail)<\/th>\n<th style=\"background: linear-gradient(135deg,#077FFA,#0C40F4); color: #ffffff; padding: 14px; border: 1px solid #e6e9f5; text-align: left;\">DMARC (Domain-based Message Authentication, Reporting &amp; Conformance)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background: #f8faff;\">\n<td style=\"padding: 14px; border: 1px solid #e6e9f5; font-weight: 600;\">C\u01a1 ch\u1ebf x\u00e1c th\u1ef1c<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">D\u1ef1a tr\u00ean \u0111\u1ecba ch\u1ec9 IP c\u1ee7a m\u00e1y ch\u1ee7 g\u1eedi.<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">D\u1ef1a tr\u00ean ch\u1eef k\u00fd s\u1ed1 m\u00e3 h\u00f3a (Cryptographic signature).<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">D\u1ef1a tr\u00ean k\u1ebft qu\u1ea3 c\u1ee7a SPF v\u00e0 DKIM.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5; font-weight: 600;\">C\u00e2u h\u1ecfi gi\u1ea3i quy\u1ebft<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">\u201cAi (IP n\u00e0o) \u0111\u01b0\u1ee3c ph\u00e9p g\u1eedi th\u01b0 cho t\u00ean mi\u1ec1n n\u00e0y?\u201d<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">\u201cEmail n\u00e0y c\u00f3 \u0111\u00fang l\u00e0 c\u1ee7a ch\u1ee7 t\u00ean mi\u1ec1n kh\u00f4ng v\u00e0 c\u00f3 b\u1ecb s\u1eeda \u0111\u1ed5i kh\u00f4ng?\u201d<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">\u201cL\u00e0m g\u00ec n\u1ebfu email vi ph\u1ea1m SPF ho\u1eb7c DKIM?\u201d<\/td>\n<\/tr>\n<tr style=\"background: #f8faff;\">\n<td style=\"padding: 14px; border: 1px solid #e6e9f5; font-weight: 600;\">V\u1ecb tr\u00ed ki\u1ec3m tra<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">Ki\u1ec3m tra phong b\u00ec th\u01b0 (Envelope From).<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">Ki\u1ec3m tra ti\u00eau \u0111\u1ec1 th\u01b0 (Message Header).<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">Quy \u0111\u1ecbnh ch\u00ednh s\u00e1ch v\u00e0 b\u00e1o c\u00e1o.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5; font-weight: 600;\">Kh\u1ea3 n\u0103ng s\u1ed1ng s\u00f3t khi Forward<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">Th\u01b0\u1eddng b\u1ecb l\u1ed7i khi email \u0111\u01b0\u1ee3c chuy\u1ec3n ti\u1ebfp (Forwarding).<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">V\u1eabn gi\u1eef nguy\u00ean gi\u00e1 tr\u1ecb khi Forward (v\u00ec ch\u1eef k\u00fd n\u1eb1m trong header).<\/td>\n<td style=\"padding: 14px; border: 1px solid #e6e9f5;\">Gi\u00fap \u0111\u1ed3ng b\u1ed9 h\u00f3a ch\u00ednh s\u00e1ch x\u1eed l\u00fd.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p><strong>Ph\u00e2n t\u00edch s\u00e2u h\u01a1n:<\/strong><\/p>\n<ul>\n<li><strong>SPF<\/strong> gi\u1ed1ng nh\u01b0 danh s\u00e1ch nh\u00e2n vi\u00ean b\u1ea3o v\u1ec7 \u0111\u01b0\u1ee3c ph\u00e9p ra v\u00e0o t\u00f2a nh\u00e0. N\u1ebfu IP g\u1eedi th\u01b0 kh\u00f4ng n\u1eb1m trong danh s\u00e1ch (b\u1ea3n ghi SPF), n\u00f3 b\u1ecb coi l\u00e0 ng\u01b0\u1eddi l\u1ea1. Tuy nhi\u00ean, SPF c\u00f3 \u0111i\u1ec3m y\u1ebfu l\u00e0 n\u1ebfu b\u1ea1n chuy\u1ec3n ti\u1ebfp (forward) email, IP ng\u01b0\u1eddi g\u1eedi thay \u0111\u1ed5i, SPF s\u1ebd b\u1ecb l\u1ed7i (Fail).<\/li>\n<li><strong>DKIM<\/strong> kh\u1eafc ph\u1ee5c \u0111i\u1ec3m y\u1ebfu c\u1ee7a SPF. V\u00ec ch\u1eef k\u00fd DKIM \u0111i k\u00e8m v\u1edbi email gi\u1ed1ng nh\u01b0 ni\u00eam phong tr\u00ean bao th\u01b0, d\u00f9 email \u0111\u00f3 \u0111\u01b0\u1ee3c chuy\u1ec3n ti\u1ebfp qua bao nhi\u00eau m\u00e1y ch\u1ee7 trung gian, mi\u1ec5n l\u00e0 n\u1ed9i dung kh\u00f4ng \u0111\u1ed5i, ch\u1eef k\u00fd v\u1eabn h\u1ee3p l\u1ec7.<\/li>\n<li><strong>DMARC<\/strong> l\u00e0 ng\u01b0\u1eddi qu\u1ea3n l\u00fd. DMARC s\u1ebd n\u00f3i v\u1edbi m\u00e1y ch\u1ee7 nh\u1eadn r\u1eb1ng: &#8220;N\u1ebfu l\u00e1 th\u01b0 n\u00e0y tr\u01b0\u1ee3t c\u1ea3 b\u00e0i ki\u1ec3m tra SPF v\u00e0 x\u00e1c th\u1ef1c DKIM, h\u00e3y v\u1ee9t n\u00f3 v\u00e0o s\u1ecdt r\u00e1c ngay l\u1eadp t\u1ee9c v\u00e0 b\u00e1o c\u00e1o l\u1ea1i cho t\u00f4i&#8221;.<\/li>\n<\/ul>\n<p>Do \u0111\u00f3, m\u1ed9t chi\u1ebfn l\u01b0\u1ee3c b\u1ea3o m\u1eadt email to\u00e0n di\u1ec7n ph\u1ea3i bao g\u1ed3m c\u1ea3 ba y\u1ebfu t\u1ed1 n\u00e0y.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Khi-nao-can-cau-hinh-DKIM\"><\/span>Khi n\u00e0o c\u1ea7n c\u1ea5u h\u00ecnh DKIM?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Nhi\u1ec1u ng\u01b0\u1eddi d\u00f9ng c\u00e1 nh\u00e2n s\u1eed d\u1ee5ng Gmail mi\u1ec5n ph\u00ed (@gmail.com) th\u01b0\u1eddng kh\u00f4ng c\u1ea7n quan t\u00e2m \u0111\u1ebfn v\u1ea5n \u0111\u1ec1 n\u00e0y v\u00ec Google \u0111\u00e3 t\u1ef1 \u0111\u1ed9ng c\u1ea5u h\u00ecnh m\u1eb7c \u0111\u1ecbnh. Tuy nhi\u00ean, b\u1ed1i c\u1ea3nh thay \u0111\u1ed5i ho\u00e0n to\u00e0n khi b\u1ea1n s\u1eed d\u1ee5ng t\u00ean mi\u1ec1n ri\u00eang.<\/p>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e1c tr\u01b0\u1eddng h\u1ee3p c\u1ee5 th\u1ec3 m\u00e0 vi\u1ec7c t\u00ecm hi\u1ec3u ti\u00eau chu\u1ea9n b\u1ea3o m\u1eadt email <strong>DKIM<\/strong>\u00a0v\u00e0 c\u1ea5u h\u00ecnh n\u00f3 l\u00e0 b\u1eaft bu\u1ed9c:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"1-Doanh-nghiep-su-dung-Email-theo-ten-mien-rieng\"><\/span>1. Doanh nghi\u1ec7p s\u1eed d\u1ee5ng Email theo t\u00ean mi\u1ec1n ri\u00eang<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Ngay khi b\u1ea1n \u0111\u0103ng k\u00fd m\u1ed9t d\u1ecbch v\u1ee5 email doanh nghi\u1ec7p, c\u1ea5u h\u00ecnh m\u1eb7c \u0111\u1ecbnh ban \u0111\u1ea7u th\u01b0\u1eddng ch\u01b0a bao g\u1ed3m DKIM ho\u1eb7c ch\u1ec9 l\u00e0 DKIM m\u1eb7c \u0111\u1ecbnh c\u1ee7a nh\u00e0 cung c\u1ea5p (v\u1edbi selector chung). \u0110\u1ec3 x\u00e2y d\u1ef1ng uy t\u00edn ri\u00eang cho t\u00ean mi\u1ec1n (Domain reputation), b\u1ea1n c\u1ea7n t\u1ea1o b\u1ea3n ghi DKIM ri\u00eang (Custom DKIM).<\/p>\n<h3><span class=\"ez-toc-section\" id=\"2-Trien-khai-cac-chien-dich-Email-Marketing\"><\/span>2. Tri\u1ec3n khai c\u00e1c chi\u1ebfn d\u1ecbch Email Marketing<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>N\u1ebfu b\u1ea1n s\u1eed d\u1ee5ng c\u00e1c c\u00f4ng c\u1ee5 b\u00ean th\u1ee9 ba nh\u01b0 Mailchimp, GetResponse, HubSpot hay h\u1ec7 th\u1ed1ng CRM \u0111\u1ec3 g\u1eedi email s\u1ed1 l\u01b0\u1ee3ng l\u1edbn, vi\u1ec7c x\u00e1c th\u1ef1c t\u00ean mi\u1ec1n l\u00e0 y\u00eau c\u1ea7u b\u1eaft bu\u1ed9c. C\u00e1c n\u1ec1n t\u1ea3ng n\u00e0y g\u1eedi email thay m\u1eb7t b\u1ea1n. N\u1ebfu kh\u00f4ng c\u00f3 DKIM (v\u00e0 SPF), c\u00e1c ISP s\u1ebd coi h\u00e0nh \u0111\u1ed9ng g\u1eedi h\u00e0ng lo\u1ea1t n\u00e0y l\u00e0 spam.<\/p>\n<figure id=\"attachment_37921\" aria-describedby=\"caption-attachment-37921\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-37921\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Khi-nao-can-cau-hinh-DKIM.jpg\" alt=\"Khi n\u00e0o c\u1ea7n c\u1ea5u h\u00ecnh DKIM\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Khi-nao-can-cau-hinh-DKIM.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Khi-nao-can-cau-hinh-DKIM-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Khi-nao-can-cau-hinh-DKIM-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-37921\" class=\"wp-caption-text\">Khi n\u00e0o c\u1ea7n c\u1ea5u h\u00ecnh DKIM?<\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"3-Website-gui-email-tu-dong-Transactional-Email\"><\/span>3. Website g\u1eedi email t\u1ef1 \u0111\u1ed9ng (Transactional Email)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>C\u00e1c website th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed, di\u1ec5n \u0111\u00e0n hay \u1ee9ng d\u1ee5ng web th\u01b0\u1eddng xuy\u00ean g\u1eedi email th\u00f4ng b\u00e1o \u0111\u01a1n h\u00e0ng, reset m\u1eadt kh\u1ea9u, m\u00e3 OTP. Nh\u1eefng email n\u00e0y c\u00f3 t\u1ef7 l\u1ec7 b\u1ecb ch\u1eb7n r\u1ea5t cao n\u1ebfu thi\u1ebfu x\u00e1c th\u1ef1c. Vi\u1ec7c c\u1ea5u h\u00ecnh DKIM gi\u00fap \u0111\u1ea3m b\u1ea3o th\u00f4ng tin quan tr\u1ecdng \u0111\u1ebfn \u0111\u01b0\u1ee3c tay ng\u01b0\u1eddi d\u00f9ng ngay l\u1eadp t\u1ee9c.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"4-Khi-nhan-thay-ty-le-mo-email-Open-Rate-giam-dot-ngot\"><\/span>4. Khi nh\u1eadn th\u1ea5y t\u1ef7 l\u1ec7 m\u1edf email (Open Rate) gi\u1ea3m \u0111\u1ed9t ng\u1ed9t<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>N\u1ebfu b\u1ea1n nh\u1eadn th\u1ea5y c\u00e1c ch\u1ec9 s\u1ed1 hi\u1ec7u qu\u1ea3 c\u1ee7a email gi\u1ea3m s\u00fat, ho\u1eb7c kh\u00e1ch h\u00e0ng ph\u1ea3n h\u1ed3i r\u1eb1ng h\u1ecd kh\u00f4ng nh\u1eadn \u0111\u01b0\u1ee3c th\u01b0, \u0111\u00f3 l\u00e0 t\u00edn hi\u1ec7u \u0111\u1ecf. L\u00fac n\u00e0y, vi\u1ec7c ki\u1ec3m tra l\u1ea1i c\u1ea5u h\u00ecnh DKIM l\u00e0 b\u01b0\u1edbc r\u00e0 so\u00e1t k\u1ef9 thu\u1eadt \u0111\u1ea7u ti\u00ean c\u1ea7n th\u1ef1c hi\u1ec7n.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cau-hinh-DKIM-cho-he-thong-mail-server\"><\/span>C\u1ea5u h\u00ecnh DKIM cho h\u1ec7 th\u1ed1ng mail server<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Vi\u1ec7c thi\u1ebft l\u1eadp DKIM ph\u1ee5 thu\u1ed9c v\u00e0o lo\u1ea1i mail server v\u00e0 n\u1ec1n t\u1ea3ng email m\u00e0 b\u1ea1n \u0111ang s\u1eed d\u1ee5ng. M\u1eb7c d\u00f9 c\u00e1ch tri\u1ec3n khai c\u00f3 th\u1ec3 kh\u00e1c nhau, nh\u01b0ng quy tr\u00ecnh t\u1ed5ng qu\u00e1t th\u01b0\u1eddng bao g\u1ed3m c\u00e1c b\u01b0\u1edbc sau.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Cach-xac-minh-DKIM-o-phia-nguoi-nhan\"><\/span>C\u00e1ch x\u00e1c minh DKIM \u1edf ph\u00eda ng\u01b0\u1eddi nh\u1eadn<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>B\u01b0\u1edbc 1:<\/strong> Nh\u1eadn email t\u1eeb domain g\u1eedi v\u00e0 ki\u1ec3m tra xem email c\u00f3 th\u00f4ng \u0111i\u1ec7p \u0111\u00e3 \u0111\u01b0\u1ee3c k\u00fd DKIM hay kh\u00f4ng.<\/p>\n<p><strong>B\u01b0\u1edbc 2:<\/strong> Truy v\u1ea5n DNS \u0111\u1ec3 l\u1ea5y <strong>Public Key c\u1ee7a t\u00ean mi\u1ec1n g\u1eedi<\/strong>, d\u00f9ng kh\u00f3a n\u00e0y \u0111\u1ec3 gi\u1ea3i m\u00e3 ch\u1eef k\u00fd DKIM.<\/p>\n<ul>\n<li>Khi gi\u1ea3i m\u00e3 th\u00e0nh c\u00f4ng, h\u1ec7 th\u1ed1ng x\u00e1c nh\u1eadn email h\u1ee3p l\u1ec7.<\/li>\n<li>N\u1ebfu gi\u1ea3i m\u00e3 kh\u00f4ng \u0111\u00fang, email s\u1ebd \u0111\u01b0\u1ee3c x\u1eed l\u00fd theo ch\u00ednh s\u00e1ch c\u1ee7a b\u00ean nh\u1eadn (t\u1eeb ch\u1ed1i ho\u1eb7c ti\u1ebfp t\u1ee5c nh\u1eadn).<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Cach-thiet-lap-DKIM-o-phia-nguoi-gui\"><\/span>C\u00e1ch thi\u1ebft l\u1eadp DKIM \u1edf ph\u00eda ng\u01b0\u1eddi g\u1eedi<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li><strong>B\u01b0\u1edbc 1:<\/strong> T\u1ea1o c\u1eb7p kh\u00f3a <strong>Private\/Public<\/strong> b\u1eb1ng c\u00e1c c\u00f4ng c\u1ee5 h\u1ed7 tr\u1ee3 nh\u01b0 OpenSSL.<\/li>\n<li><strong>B\u01b0\u1edbc 2:<\/strong> \u0110\u01b0a <strong>Public Key<\/strong> l\u00ean DNS d\u01b0\u1edbi d\u1ea1ng b\u1ea3n ghi TXT, t\u01b0\u01a1ng \u1ee9ng v\u1edbi domain g\u1eedi email.<\/li>\n<li><strong>B\u01b0\u1edbc 3:<\/strong> C\u1ea5u h\u00ecnh mail server s\u1eed d\u1ee5ng <strong>Private Key<\/strong> \u0111\u1ec3 k\u00fd DKIM cho t\u1ea5t c\u1ea3 email tr\u01b0\u1edbc khi g\u1eedi \u0111i.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Huong-dan-cai-dat-DKIM-tren-Microsoft-365-Defender\"><\/span>H\u01b0\u1edbng d\u1eabn c\u00e0i \u0111\u1eb7t DKIM tr\u00ean Microsoft 365 Defender<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>X\u00e1c th\u1ef1c DKIM \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c h\u1ea1n ch\u1ebf th\u01b0 r\u00e1c, email l\u1eeba \u0111\u1ea3o v\u00e0 t\u0103ng c\u01b0\u1eddng b\u1ea3o m\u1eadt trong m\u00f4i tr\u01b0\u1eddng <strong>Microsoft 365 Defender<\/strong>. \u0110\u1ec3 c\u1ea5u h\u00ecnh DKIM tr\u00ean n\u1ec1n t\u1ea3ng n\u00e0y, ng\u01b0\u1eddi d\u00f9ng c\u1ea7n th\u1ef1c hi\u1ec7n l\u1ea7n l\u01b0\u1ee3t c\u00e1c b\u01b0\u1edbc sau.<\/p>\n<ul>\n<li><strong>B\u01b0\u1edbc 1:<\/strong> \u0110\u0103ng nh\u1eadp v\u00e0o trang qu\u1ea3n tr\u1ecb <strong>Microsoft 365 Defender<\/strong>, ch\u1ecdn t\u00ean mi\u1ec1n c\u1ea7n c\u1ea5u h\u00ecnh v\u00e0 ti\u1ebfn h\u00e0nh t\u1ea1o kh\u00f3a DKIM.<\/li>\n<li><strong>B\u01b0\u1edbc 2:<\/strong> T\u1ea1i khu v\u1ef1c c\u1ea5u h\u00ecnh DKIM, h\u1ec7 th\u1ed1ng s\u1ebd t\u1ea1o m\u1ed9t c\u1eb7p kh\u00f3a g\u1ed3m <strong>kh\u00f3a ri\u00eang v\u00e0 kh\u00f3a c\u00f4ng khai<\/strong>. Ng\u01b0\u1eddi d\u00f9ng c\u1ea7n sao l\u01b0u c\u00e1c kh\u00f3a n\u00e0y v\u00e0 \u0111\u1ea3m b\u1ea3o <strong>kh\u00f3a ri\u00eang \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt tuy\u1ec7t \u0111\u1ed1i<\/strong>.<\/li>\n<li><strong>B\u01b0\u1edbc 3:<\/strong> \u0110\u0103ng nh\u1eadp v\u00e0o h\u1ec7 th\u1ed1ng qu\u1ea3n l\u00fd DNS c\u1ee7a nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 DNS \u0111ang s\u1eed d\u1ee5ng.<\/li>\n<li><strong>B\u01b0\u1edbc 4:<\/strong> Trong giao di\u1ec7n DNS, th\u00eam m\u1ed9t <strong>b\u1ea3n ghi TXT cho DKIM<\/strong>, nh\u1eadp \u0111\u1ea7y \u0111\u1ee7 th\u00f4ng tin bao g\u1ed3m t\u00ean mi\u1ec1n v\u00e0 <strong>Public Key DKIM<\/strong> \u0111\u00e3 t\u1ea1o \u1edf b\u01b0\u1edbc tr\u01b0\u1edbc.<\/li>\n<li><strong>B\u01b0\u1edbc 5:<\/strong> Sau khi ho\u00e0n t\u1ea5t vi\u1ec7c th\u00eam b\u1ea3n ghi DKIM trong DNS, quay l\u1ea1i Microsoft 365 Defender v\u00e0 <strong>k\u00edch ho\u1ea1t DKIM cho t\u00ean mi\u1ec1n<\/strong>.<\/li>\n<\/ul>\n<p>Khi c\u00e1c b\u01b0\u1edbc tr\u00ean \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n \u0111\u1ea7y \u0111\u1ee7, DKIM s\u1ebd \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng cho domain, gi\u00fap \u0111\u1ea3m b\u1ea3o <strong>t\u00ednh to\u00e0n v\u1eb9n v\u00e0 x\u00e1c th\u1ef1c c\u1ee7a email<\/strong> \u0111\u01b0\u1ee3c g\u1eedi t\u1eeb t\u00ean mi\u1ec1n \u0111\u00f3.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cac-loi-thuong-gap-khi-cai-dat-DKIM\"><\/span>C\u00e1c l\u1ed7i th\u01b0\u1eddng g\u1eb7p khi c\u00e0i \u0111\u1eb7t DKIM<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>D\u00f9 kh\u00e1i ni\u1ec7m c\u00f3 v\u1ebb \u0111\u01a1n gi\u1ea3n, nh\u01b0ng qu\u00e1 tr\u00ecnh tri\u1ec3n khai DKIM th\u01b0\u1eddng g\u1eb7p nhi\u1ec1u v\u01b0\u1edbng m\u1eafc k\u1ef9 thu\u1eadt. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 nh\u1eefng l\u1ed7i ph\u1ed5 bi\u1ebfn:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"1-Copy-thieu-hoac-sai-ky-tu-trong-chuoi-ma-hoa\"><\/span>1. Copy thi\u1ebfu ho\u1eb7c sai k\u00fd t\u1ef1 trong chu\u1ed7i m\u00e3 h\u00f3a<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Public Key c\u1ee7a DKIM l\u00e0 m\u1ed9t chu\u1ed7i k\u00fd t\u1ef1 ng\u1eabu nhi\u00ean r\u1ea5t d\u00e0i (c\u00f3 th\u1ec3 l\u00ean t\u1edbi 1024-bit ho\u1eb7c 2048-bit). Vi\u1ec7c copy thi\u1ebfu m\u1ed9t k\u00fd t\u1ef1 cu\u1ed1i c\u00f9ng, ho\u1eb7c th\u1eeba kho\u1ea3ng tr\u1eafng (space) khi d\u00e1n v\u00e0o b\u1ea3n ghi DNS l\u00e0 l\u1ed7i ph\u1ed5 bi\u1ebfn nh\u1ea5t. \u0110i\u1ec1u n\u00e0y l\u00e0m cho Public Key tr\u00ean DNS kh\u00f4ng kh\u1edbp v\u1edbi Private Key tr\u00ean server, d\u1eabn \u0111\u1ebfn k\u1ebft qu\u1ea3 <strong>DKIM Fail<\/strong>.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"2-DNS-chua-cap-nhat-Propagation-Delay\"><\/span>2. DNS ch\u01b0a c\u1eadp nh\u1eadt (Propagation Delay)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Sau khi th\u00eam b\u1ea3n ghi TXT v\u00e0o DNS, h\u1ec7 th\u1ed1ng to\u00e0n c\u1ea7u c\u1ea7n m\u1ed9t kho\u1ea3ng th\u1eddi gian \u0111\u1ec3 c\u1eadp nh\u1eadt (t\u1eeb 1 gi\u1edd \u0111\u1ebfn 24 gi\u1edd). Nhi\u1ec1u ng\u01b0\u1eddi d\u00f9ng v\u1eeba c\u1ea5u h\u00ecnh xong \u0111\u00e3 v\u1ed9i v\u00e0ng ki\u1ec3m tra ngay v\u00e0 th\u1ea5y b\u00e1o l\u1ed7i, d\u1eabn \u0111\u1ebfn vi\u1ec7c s\u1eeda \u0111i s\u1eeda l\u1ea1i c\u1ea5u h\u00ecnh \u0111ang \u0111\u00fang th\u00e0nh sai.<\/p>\n<p>L\u1eddi khuy\u00ean: H\u00e3y ki\u00ean nh\u1eabn ch\u1edd \u0111\u1ee3i ho\u1eb7c s\u1eed d\u1ee5ng c\u00e1c c\u00f4ng c\u1ee5 ki\u1ec3m tra DNS tr\u1ef1c ti\u1ebfp t\u1ea1i m\u00e1y ch\u1ee7 ph\u00e2n gi\u1ea3i (Nameserver) \u0111\u1ec3 x\u00e1c nh\u1eadn.<\/p>\n<figure id=\"attachment_37924\" aria-describedby=\"caption-attachment-37924\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-37924\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Cac-loi-thuong-gap-khi-cai-dat-DKIM.jpg\" alt=\"C\u00e1c l\u1ed7i th\u01b0\u1eddng g\u1eb7p khi c\u00e0i \u0111\u1eb7t DKIM\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Cac-loi-thuong-gap-khi-cai-dat-DKIM.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Cac-loi-thuong-gap-khi-cai-dat-DKIM-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2026\/01\/Cac-loi-thuong-gap-khi-cai-dat-DKIM-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-37924\" class=\"wp-caption-text\">C\u00e1c l\u1ed7i th\u01b0\u1eddng g\u1eb7p khi c\u00e0i \u0111\u1eb7t DKIM<\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"3-Sai-Selector-Bo-dinh-danh\"><\/span>3. Sai Selector (B\u1ed9 \u0111\u1ecbnh danh)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1ed7i b\u1ea3n ghi DKIM \u0111i k\u00e8m v\u1edbi m\u1ed9t &#8220;Selector&#8221; (v\u00ed d\u1ee5: google._domainkey ho\u1eb7c default._domainkey). M\u00e1y ch\u1ee7 g\u1eedi email s\u1ebd ch\u1ec9 \u0111\u1ecbnh selector n\u00e0o \u0111\u01b0\u1ee3c d\u00f9ng trong header. N\u1ebfu b\u1ea1n c\u1ea5u h\u00ecnh tr\u00ean DNS l\u00e0 selector1 nh\u01b0ng m\u00e1y ch\u1ee7 mail l\u1ea1i g\u1eedi \u0111i v\u1edbi th\u00f4ng tin ch\u1ec9 d\u1eabn l\u00e0 selectorA, qu\u00e1 tr\u00ecnh kh\u1edbp kh\u00f3a s\u1ebd th\u1ea5t b\u1ea1i. B\u1ea1n c\u1ea7n \u0111\u1ea3m b\u1ea3o t\u00ean Selector tr\u00ean DNS tr\u00f9ng kh\u1edbp ch\u00ednh x\u00e1c v\u1edbi c\u1ea5u h\u00ecnh trong trang qu\u1ea3n tr\u1ecb email.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"4-Do-dai-khoa-vuot-qua-gioi-han-cua-nha-cung-cap-DNS\"><\/span>4. \u0110\u1ed9 d\u00e0i kh\u00f3a v\u01b0\u1ee3t qu\u00e1 gi\u1edbi h\u1ea1n c\u1ee7a nh\u00e0 cung c\u1ea5p DNS<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1ed9t s\u1ed1 nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 DNS \u0111\u1eddi c\u0169 gi\u1edbi h\u1ea1n \u0111\u1ed9 d\u00e0i c\u1ee7a b\u1ea3n ghi TXT \u1edf m\u1ee9c 255 k\u00fd t\u1ef1. Trong khi \u0111\u00f3, kh\u00f3a DKIM 2048-bit th\u01b0\u1eddng d\u00e0i h\u01a1n m\u1ee9c n\u00e0y.<\/p>\n<p>C\u00e1ch kh\u1eafc ph\u1ee5c: B\u1ea1n c\u1ea7n chia t\u00e1ch b\u1ea3n ghi DKIM th\u00e0nh hai ph\u1ea7n n\u1ed1i ti\u1ebfp nhau ho\u1eb7c chuy\u1ec3n sang s\u1eed d\u1ee5ng c\u00e1c nh\u00e0 cung c\u1ea5p DNS hi\u1ec7n \u0111\u1ea1i h\u01a1n nh\u01b0 Cloudflare ho\u1eb7c h\u1ec7 th\u1ed1ng DNS c\u1ee7a InterData.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"5-Xung-dot-nhieu-ban-ghi-DKIM\"><\/span>5. Xung \u0111\u1ed9t nhi\u1ec1u b\u1ea3n ghi DKIM<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>M\u1ed9t t\u00ean mi\u1ec1n c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u b\u1ea3n ghi DKIM (cho nhi\u1ec1u d\u1ecbch v\u1ee5 g\u1eedi mail kh\u00e1c nhau nh\u01b0 Google, Mailchimp, Amazon SES&#8230;). Tuy nhi\u00ean, m\u1ed7i d\u1ecbch v\u1ee5 ph\u1ea3i s\u1eed d\u1ee5ng m\u1ed9t <strong>Selector kh\u00e1c nhau<\/strong>. N\u1ebfu b\u1ea1n c\u1ed1 g\u1eafng g\u00e1n hai gi\u00e1 tr\u1ecb Public Key kh\u00e1c nhau v\u00e0o c\u00f9ng m\u1ed9t Selector, h\u1ec7 th\u1ed1ng s\u1ebd b\u1ecb xung \u0111\u1ed9t v\u00e0 kh\u00f4ng th\u1ec3 x\u00e1c th\u1ef1c.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cau-hoi-thuong-gap-ve-DKIM-FAQ\"><\/span>C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 DKIM (FAQ)<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Ph\u1ea7n n\u00e0y s\u1ebd gi\u1ea3i \u0111\u00e1p nhanh c\u00e1c th\u1eafc m\u1eafc ng\u1eafn g\u1ecdn li\u00ean quan \u0111\u1ebfn ch\u1ee7 \u0111\u1ec1 ti\u00eau chu\u1ea9n b\u1ea3o m\u1eadt email DKIM\u00a0v\u00e0 qu\u00e1 tr\u00ecnh v\u1eadn h\u00e0nh th\u1ef1c t\u1ebf.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Khong-co-DKIM-email-co-gui-duoc-khong\"><\/span>Kh\u00f4ng c\u00f3 DKIM email c\u00f3 g\u1eedi \u0111\u01b0\u1ee3c kh\u00f4ng?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> C\u00f3, email v\u1eabn c\u00f3 th\u1ec3 g\u1eedi \u0111i \u0111\u01b0\u1ee3c. Tuy nhi\u00ean, email \u0111\u00f3 s\u1ebd thi\u1ebfu s\u1ef1 x\u00e1c th\u1ef1c. C\u00e1c h\u1ec7 th\u1ed1ng nh\u1eadn th\u01b0 kh\u1eaft khe (nh\u01b0 Gmail doanh nghi\u1ec7p, h\u1ec7 th\u1ed1ng t\u01b0\u1eddng l\u1eeda c\u1ee7a c\u00f4ng ty l\u1edbn) c\u00f3 th\u1ec3 ch\u1eb7n email c\u1ee7a b\u1ea1n ho\u1eb7c \u0111\u01b0a v\u00e0o Spam. Uy t\u00edn t\u00ean mi\u1ec1n c\u1ee7a b\u1ea1n s\u1ebd b\u1ecb \u1ea3nh h\u01b0\u1edfng ti\u00eau c\u1ef1c theo th\u1eddi gian.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"DKIM-co-thay-the-duoc-SPF-khong\"><\/span>DKIM c\u00f3 thay th\u1ebf \u0111\u01b0\u1ee3c SPF kh\u00f4ng?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Kh\u00f4ng. DKIM v\u00e0 SPF gi\u1ea3i quy\u1ebft hai b\u00e0i to\u00e1n kh\u00e1c nhau (nh\u01b0 \u0111\u00e3 ph\u00e2n t\u00edch \u1edf ph\u1ea7n so s\u00e1nh). B\u1ea1n n\u00ean s\u1eed d\u1ee5ng k\u1ebft h\u1ee3p c\u1ea3 hai \u0111\u1ec3 \u0111\u1ea1t hi\u1ec7u qu\u1ea3 t\u1ed1i \u01b0u. Google v\u00e0 Yahoo hi\u1ec7n t\u1ea1i khuy\u1ebfn ngh\u1ecb m\u1ea1nh m\u1ebd vi\u1ec7c c\u00f3 c\u1ea3 SPF v\u00e0 DKIM.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"DKIM-co-giup-email-vao-Inbox-100-khong\"><\/span>DKIM c\u00f3 gi\u00fap email v\u00e0o Inbox 100% kh\u00f4ng?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Kh\u00f4ng c\u00f3 b\u1ea5t k\u1ef3 k\u1ef9 thu\u1eadt n\u00e0o \u0111\u1ea3m b\u1ea3o 100% v\u00e0o Inbox. DKIM ch\u1ec9 l\u00e0 \u0111i\u1ec1u ki\u1ec7n c\u1ea7n (v\u1ec1 m\u1eb7t k\u1ef9 thu\u1eadt). Vi\u1ec7c email v\u00e0o Inbox c\u00f2n ph\u1ee5 thu\u1ed9c v\u00e0o n\u1ed9i dung email (c\u00f3 ch\u1ee9a t\u1eeb kh\u00f3a spam kh\u00f4ng), l\u1ecbch s\u1eed g\u1eedi th\u01b0 c\u1ee7a t\u00ean mi\u1ec1n, h\u00e0nh vi t\u01b0\u01a1ng t\u00e1c c\u1ee7a ng\u01b0\u1eddi nh\u1eadn v\u00e0 ch\u1ea5t l\u01b0\u1ee3ng danh s\u00e1ch email. Tuy nhi\u00ean, c\u00f3 DKIM s\u1ebd t\u0103ng c\u01a1 h\u1ed9i v\u00e0o Inbox l\u00ean m\u1ee9c cao nh\u1ea5t c\u00f3 th\u1ec3.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Toi-co-can-thay-doi-ma-DKIM-dinh-ky-khong-Key-Rotation\"><\/span>T\u00f4i c\u00f3 c\u1ea7n thay \u0111\u1ed5i m\u00e3 DKIM \u0111\u1ecbnh k\u1ef3 kh\u00f4ng (Key Rotation)?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> C\u00f3, \u0111\u00e2y l\u00e0 m\u1ed9t th\u1ef1c h\u00e0nh b\u1ea3o m\u1eadt t\u1ed1t (Security Best Practice). B\u1ea1n n\u00ean thay \u0111\u1ed5i c\u1eb7p kh\u00f3a DKIM (g\u1ecdi l\u00e0 Key Rotation) \u0111\u1ecbnh k\u1ef3 6 th\u00e1ng ho\u1eb7c 1 n\u0103m m\u1ed9t l\u1ea7n. Vi\u1ec7c n\u00e0y gi\u00fap gi\u1ea3m thi\u1ec3u r\u1ee7i ro trong tr\u01b0\u1eddng h\u1ee3p Private Key b\u1ecb l\u1ed9 l\u1ecdt ra ngo\u00e0i. C\u00e1c d\u1ecbch v\u1ee5 nh\u01b0 Google Workspace hay Office 365 th\u01b0\u1eddng h\u1ed7 tr\u1ee3 quy tr\u00ecnh n\u00e0y kh\u00e1 d\u1ec5 d\u00e0ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Ket-luan\"><\/span>K\u1ebft lu\u1eadn<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Qua b\u00e0i vi\u1ebft n\u00e0y, hy v\u1ecdng b\u1ea1n \u0111\u00e3 n\u1eafm v\u1eefng <strong>DKIM l\u00e0 g\u00ec<\/strong> v\u00e0 t\u1ea7m quan tr\u1ecdng kh\u00f4ng th\u1ec3 thay th\u1ebf c\u1ee7a n\u00f3 trong h\u1ea1 t\u1ea7ng email doanh nghi\u1ec7p. DKIM kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t c\u1ea5u h\u00ecnh k\u1ef9 thu\u1eadt kh\u00f4 khan, m\u00e0 l\u00e0 &#8220;t\u1ea5m khi\u00ean&#8221; b\u1ea3o v\u1ec7 th\u01b0\u01a1ng hi\u1ec7u v\u00e0 l\u00e0 &#8220;t\u1ea5m v\u00e9 th\u00f4ng h\u00e0nh&#8221; gi\u00fap th\u00f4ng \u0111i\u1ec7p c\u1ee7a b\u1ea1n ti\u1ebfp c\u1eadn kh\u00e1ch h\u00e0ng m\u1ed9t c\u00e1ch an to\u00e0n.<\/p>\n<p>Vi\u1ec7c c\u1ea5u h\u00ecnh DKIM tuy \u0111\u00f2i h\u1ecfi s\u1ef1 t\u1ec9 m\u1ec9 v\u00e0 hi\u1ec3u bi\u1ebft nh\u1ea5t \u0111\u1ecbnh v\u1ec1 DNS, nh\u01b0ng k\u1ebft qu\u1ea3 mang l\u1ea1i cho hi\u1ec7u su\u1ea5t g\u1eedi email l\u00e0 v\u00f4 c\u00f9ng x\u1ee9ng \u0111\u00e1ng. InterData khuy\u1ebfn ngh\u1ecb b\u1ea1n n\u00ean r\u00e0 so\u00e1t l\u1ea1i h\u1ec7 th\u1ed1ng email ngay h\u00f4m nay v\u00e0 \u0111\u1ea3m b\u1ea3o r\u1eb1ng b\u1ed9 ba <strong>SPF \u2013 DKIM \u2013 DMARC<\/strong> \u0111\u00e3 \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp ch\u00ednh x\u00e1c.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>B\u1ea1n g\u1eedi email b\u00e1o gi\u00e1 cho \u0111\u1ed1i t\u00e1c nh\u01b0ng h\u1ecd ph\u1ea3n h\u1ed3i r\u1eb1ng ch\u01b0a nh\u1eadn \u0111\u01b0\u1ee3c, ho\u1eb7c t\u1ec7 h\u01a1n l\u00e0 email n\u1eb1m trong h\u00f2m th\u01b0 Spam? T\u1ea1i InterData, ch\u00fang t\u00f4i hi\u1ec3u r\u1eb1ng vi\u1ec7c email b\u1ecb \u0111\u00e1nh d\u1ea5u l\u00e0 kh\u00f4ng an to\u00e0n \u1ea3nh h\u01b0\u1edfng nghi\u00eam tr\u1ecdng \u0111\u1ebfn uy t\u00edn doanh nghi\u1ec7p. Gi\u1ea3i ph\u00e1p c\u1ed1t l\u00f5i cho<\/p>\n","protected":false},"author":11,"featured_media":37925,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[83],"tags":[],"class_list":["post-37912","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bao-mat-an-ninh-mang"],"_links":{"self":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/37912","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\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/comments?post=37912"}],"version-history":[{"count":4,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/37912\/revisions"}],"predecessor-version":[{"id":38628,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/37912\/revisions\/38628"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media\/37925"}],"wp:attachment":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media?parent=37912"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/categories?post=37912"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/tags?post=37912"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}