{"id":2686,"date":"2026-07-20T14:09:45","date_gmt":"2026-07-20T06:09:45","guid":{"rendered":"https:\/\/yanxu.guilinkeji.com\/dns-records-https-email-cdn-guide.html"},"modified":"2026-07-20T14:19:42","modified_gmt":"2026-07-20T06:19:42","slug":"dns-records-https-email-cdn-guide","status":"publish","type":"post","link":"https:\/\/yanxu.guilinkeji.com\/en\/dns-records-https-email-cdn-guide.html","title":{"rendered":"DNS and HTTPS: Connecting Your Website, Email and CDN"},"content":{"rendered":"<style>\nhtml,body{max-width:100%;overflow-x:hidden}.single-hero-outside{display:none!important}.yfg{--ink:#172033;--muted:#667085;--line:#dce3eb;--soft:#f3f6f8;--green:#168b68;--blue:#4064f4;color:var(--ink);font-family:\"Microsoft YaHei\",\"PingFang SC\",Arial,sans-serif;width:100vw;margin-left:calc(50% - 50vw);background:#fff;letter-spacing:0}.yfg *{box-sizing:border-box;letter-spacing:0}.yfg a{text-decoration:none}.yfg-wrap{width:min(1120px,calc(100% - 40px));margin:auto}.yfg-hero{padding:76px 0 58px;border-bottom:1px solid var(--line);background:#fff}.yfg-hero-grid{display:grid;grid-template-columns:minmax(0,1fr) 290px;gap:72px;align-items:start}.yfg-label{display:inline-flex;color:var(--green);font-size:12px;font-weight:800;letter-spacing:1.4px!important;margin-bottom:18px}.yfg h1{font-size:48px;line-height:1.16;margin:0 0 18px}.yfg-lead{font-size:17px;line-height:1.85;color:var(--muted);max-width:760px;margin:0}.yfg-meta{display:flex;gap:18px;flex-wrap:wrap;margin-top:22px;font-size:13px;color:#526074}.yfg-aside{border:1px solid var(--line);background:#f7f9fa;padding:22px;border-radius:7px}.yfg-aside strong{display:block;margin-bottom:12px}.yfg-aside ul{padding-left:18px;margin:0;color:#526074;line-height:1.85;font-size:13px}.yfg-body{background:var(--soft);padding-bottom:80px}.yfg-overview{display:grid;grid-template-columns:repeat(4,1fr);border-left:1px solid var(--line);border-top:1px solid var(--line);transform:translateY(-1px)}.yfg-overview article{background:#fff;padding:24px;border-right:1px solid var(--line);border-bottom:1px solid var(--line);min-height:155px}.yfg-overview b{font-size:12px;color:var(--blue)}.yfg-overview h2{font-size:19px;margin:16px 0 8px}.yfg-overview p{font-size:13px;line-height:1.65;color:var(--muted);margin:0}.yfg-conclusion{margin:38px auto 0;background:#e7f5ef;border-left:4px solid var(--green);padding:24px 26px;width:min(920px,calc(100% - 40px))}.yfg-conclusion strong{display:block;color:#117456;margin-bottom:7px}.yfg-conclusion p{margin:0;line-height:1.8;color:#3e6255}.yfg-section{padding:46px 0;border-bottom:1px solid var(--line)}.yfg-section:last-child{border-bottom:0}.yfg-content{width:min(920px,calc(100% - 40px));margin:auto}.yfg-section h2{font-size:28px;line-height:1.35;margin:0 0 14px}.yfg-section>div>p{color:#4f5b6c;line-height:1.9;margin:0}.yfg-section ul{padding-left:22px;color:#4f5b6c;line-height:1.9;margin:18px 0 0}.yfg-table{width:100%;border-collapse:collapse;background:#fff;margin-top:24px;font-size:14px}.yfg-table th,.yfg-table td{padding:15px 16px;border:1px solid var(--line);text-align:left;vertical-align:top;line-height:1.65}.yfg-table th{background:#e8f3ef;color:#244d40}.yfg-step-phase{margin:30px 0 12px;color:var(--green);font-size:13px;font-weight:800}.yfg-step-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}.yfg-step{background:#fff;border:1px solid var(--line);padding:20px;display:grid;grid-template-columns:42px 1fr;gap:15px;align-items:start}.yfg-step b{width:36px;height:36px;display:flex;align-items:center;justify-content:center;background:var(--ink);color:#fff;border-radius:50%;font-size:12px}.yfg-step h3{font-size:18px;margin:0 0 7px}.yfg-step p{font-size:13px;color:var(--muted);line-height:1.7;margin:0}.yfg-checks{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-top:22px}.yfg-check{background:#fff;border:1px solid var(--line);padding:17px 18px;display:flex;gap:11px;line-height:1.6}.yfg-check b{color:var(--green)}.yfg-faq details{background:#fff;border:1px solid var(--line);margin-top:10px;padding:17px 19px}.yfg-faq summary{font-weight:700;cursor:pointer}.yfg-faq p{color:var(--muted);line-height:1.8;margin:13px 0 0}.yfg-next{background:var(--ink);color:#fff;padding:34px 0}.yfg-next-inner{display:flex;justify-content:space-between;align-items:center;gap:24px}.yfg-next h2{font-size:24px;margin:0 0 7px;color:#fff}.yfg-next p{color:#bec7d4;margin:0}.yfg-next a{display:inline-flex;padding:12px 18px;border:1px solid rgba(255,255,255,.42);color:#fff;border-radius:5px;font-weight:700;white-space:nowrap}@media(max-width:760px){.yfg-hero{padding:52px 0 38px}.yfg-hero-grid{grid-template-columns:1fr;gap:25px}.yfg h1{font-size:34px}.yfg-lead{font-size:15px}.yfg-overview{grid-template-columns:1fr 1fr}.yfg-overview article{min-height:145px;padding:20px}.yfg-section{padding:38px 0}.yfg-section h2{font-size:23px}.yfg-table{display:block;overflow-x:auto;white-space:normal}.yfg-table th,.yfg-table td{min-width:160px}.yfg-step-grid,.yfg-checks{grid-template-columns:1fr}.yfg-next-inner{display:block}.yfg-next a{margin-top:18px}}\n<\/style><article class=\"yfg\"><header class=\"yfg-hero\"><div class=\"yfg-wrap yfg-hero-grid\"><div><span class=\"yfg-label\">DNS &amp; HTTPS<\/span><h1>DNS and HTTPS: Connecting Your Website, Email and CDN<\/h1><p class=\"yfg-lead\">Explain the purpose of A, CNAME, MX, TXT, NS and other records, and explain the correct methods for HTTPS, mail verification, CDN, resolution, and migration switching.<\/p><div class=\"yfg-meta\"><span>Technical Capabilities<\/span><span>Basic deployment and long-term maintenance<\/span><span>Original finishing<\/span><\/div><\/div><aside class=\"yfg-aside\"><strong>Who This Is For<\/strong><ul><li>Customers who need to connect the domain name to the new website<\/li><li>Teams that are configuring corporate mailboxes or CDNs<\/li><li>Administrators who need to migrate servers and reduce interruptions<\/li><\/ul><\/aside><\/div><\/header><div class=\"yfg-body\"><div class=\"yfg-wrap yfg-overview\"><article><b>A<\/b><h2>Website address<\/h2><p>Point the domain name to the IPv4 server address.<\/p><\/article><article><b>CNAME<\/b><h2>Alias and CDN<\/h2><p>Point the subdomain to another domain name or service address.<\/p><\/article><article><b>MX\/TXT<\/b><h2>Enterprise mailbox<\/h2><p>Configure the receiving server and SPF, DKIM, DMARC verification.<\/p><\/article><article><b>HTTPS<\/b><h2>Encrypted access<\/h2><p>The certificate, domain name, and server configuration must match each other.<\/p><\/article><\/div><div class=\"yfg-conclusion\"><strong>Key Takeaway<\/strong><p>DNS is the basic configuration used by websites, mailboxes, and third-party services.Backing up records before modification, reducing TTL, and verifying in stages can reduce interruptions more than blindly and repeatedly modifying.<\/p><\/div><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>Quick check of common DNS records<\/h2><p>The same domain name can have a website, mailbox, and verification records at the same time, and cannot keep only one A record.<\/p><table class=\"yfg-table\"><thead><tr><th>Record<\/th><th>Main purpose<\/th><th>Common examples<\/th><th>Precautions<\/th><\/tr><\/thead><tbody><tr><td>A \/ AAAA<\/td><td>Point to the IPv4\/IPv6 server<\/td><td>@ \u2192 203.0.113.10<\/td><td>Need to be updated after the server is replaced; pay attention to the proxy\/CDN status<\/td><\/tr><tr><td>CNAME<\/td><td>Set an alias for the subdomain<\/td><td>www \u2192 example.com<\/td><td>Usually cannot coexist with other records of the same name<\/td><\/tr><tr><td>MX<\/td><td>Specify the mail receiving server<\/td><td>@ \u2192 mail.example.com<\/td><td>The smaller the priority value, the more priority is usually given<\/td><\/tr><tr><td>TXT<\/td><td>Domain name verification and email security<\/td><td>SPF\u3001DKIM\u3001DMARC<\/td><td>Multiple SPFS cannot be simply added repeatedly<\/td><\/tr><tr><td>NS<\/td><td>Designated authoritative DNS service provider<\/td><td>ns1.provider.com<\/td><td>Switching NS is equivalent to switching the complete set of resolution management<\/td><\/tr><tr><td>CAA<\/td><td>Restrict the institutions that can issue certificates<\/td><td>letsencrypt.org<\/td><td>Incorrect configuration may cause the certificate to fail to be issued<\/td><\/tr><\/tbody><\/table><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>1. First confirm who manages the DNS<\/h2><p>Domain name registrars and DNS service providers can be different.Viewing the current NS record can determine the analysis platform that is really in effect.Don't modify records on the wrong platform, and don't switch NS directly when there is no backup.<\/p><ul><li>Record the current NS service provider<\/li><li>Export or screenshot all analysis records<\/li><li>Confirm website, mailbox, verification and CDN dependencies<\/li><li>Prepare the account administrator that can be contacted<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>2. How to configure the root domain name and www<\/h2><p>The common solution is that the root domain name uses A record to point to the server, and www uses CNAME to point to the root domain name or CDN.Only one main address is retained inside the website, and the other jumps through 301 to avoid duplicate content and confusion in login status.<\/p><ul><li>Determine the form of the main domain name<\/li><li>The certificate covers two addresses at the same time<\/li><li>The WordPress address is consistent with the jump<\/li><li>The site map only outputs the main address<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>3. Why the resolution will not take effect immediately<\/h2><p>DNS records will be cached by the network at all levels, and TTL determines the cache time.The TTL can be reduced in advance before modification, and then restored after the switch is completed and stabilized.Repeated modifications will make troubleshooting more difficult.<\/p><ul><li>Distinguish between local cache and authoritative records<\/li><li>Use multiple networks and public DNS to check<\/li><li>Don't just use the browser to refresh the judgment<\/li><li>Record the time and content of each modification<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>4. HTTPS certificate and redirect<\/h2><p>The domain name needs to be correctly pointed to the verification environment before the certificate is issued.After the certificate takes effect, configure the HTTP to HTTPS, www unified and application layer addresses to avoid the redirect loop.<\/p><ul><li>The certificate covers the root domain name and www<\/li><li>Check the automatic renewal task<\/li><li>CDN is consistent with the source station certificate mode<\/li><li>Processing mixed content of pictures and scripts<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>5. Corporate mailboxes cannot delete MX and TXT by mistake<\/h2><p>When migrating a website, only modify the relevant records of the website.MX, SPF, DKIM, DMARC, and mailbox verification TXT belong to the mail system. Accidental deletion will cause the receipt to fail or the mail to enter the trash can.<\/p><ul><li>Backup mail records before migration<\/li><li>SPF keep one and merge authorized sources<\/li><li>DKIM is configured according to the value provided by the mail platform<\/li><li>DMARC first observe and then gradually tighten the strategy<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>6. The relationship between CDN, proxy, and source station<\/h2><p>After CDN is enabled, the public DNS may point to the CDN instead of the source station IP.Troubleshooting requires checking domain name resolution, CDN status, source station certificate, and source station firewall separately.<\/p><ul><li>Save the real address of the source station<\/li><li>Restrict the source station to only allow trusted access and leave the management entrance<\/li><li>Cache refresh and DNS take effect are two things<\/li><li>Payment and background paths bypass the cache as needed<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>7. How to reduce interruptions in server migration<\/h2><p>Copy the website and database before migration, and complete the test at the temporary address; reduce the TTL in advance; keep the old server for a period of time after switching resolution, and check forms, orders, emails, and third-party callbacks.<\/p><ul><li>Test before switching<\/li><li>Pause high-risk writing before switching<\/li><li>Short-term parallel between old and new servers<\/li><li>Confirm that the logs and data are not missing<\/li><\/ul><\/div><\/section><section class=\"yfg-section\"><div class=\"yfg-content\"><h2>online and delivery checklist<\/h2><p>The following items should have clear results or records, not just the verbal description of \u201calready configured\u201d.<\/p><div class=\"yfg-checks\"><div class=\"yfg-check\"><b>\u2713<\/b><span>The current authoritative DNS platform has been confirmed<\/span><\/div><div class=\"yfg-check\"><b>\u2713<\/b><span>All DNS records have been backed up<\/span><\/div><div class=\"yfg-check\"><b>\u2713<\/b><span>Website and mailbox records are identified separately<\/span><\/div><div class=\"yfg-check\"><b>\u2713<\/b><span>HTTPS certificate and jump are normal<\/span><\/div><div class=\"yfg-check\"><b>\u2713<\/b><span>SPF\/DKIM\/DMARC verification passed<\/span><\/div><div class=\"yfg-check\"><b>\u2713<\/b><span>Complete multi-network and mobile terminal inspection after migration<\/span><\/div><\/div><\/div><\/section><section class=\"yfg-section yfg-faq\"><div class=\"yfg-content\"><h2>Frequently asked questions<\/h2><details><summary>What Is the Difference Between an A Record and a CNAME?<\/summary><p>An A record points directly to an IP address, while a CNAME points to another hostname. Root domains commonly use A records; www and service subdomains commonly use CNAME records.<\/p><\/details><details><summary>How long will the DNS modification take effect?<\/summary><p>It may be a few minutes, or it may be close to the original TTL cache time.NS switching usually has a wider impact than single record modification.<\/p><\/details><details><summary>The website is normal but the mailbox cannot receive letters. What should I check first?<\/summary><p>Check whether MX exists and the target value is correct, and then check SPF\/DKIM\/DMARC and mail service status.<\/p><\/details><details><summary>Why is the certificate reporting an error after the CDN is turned on?<\/summary><p>The common reason is that the CDN certificate, the origin certificate, and the encryption mode do not match, or the DNS still points to the old service.<\/p><\/details><\/div><\/section><\/div><footer class=\"yfg-next\"><div class=\"yfg-wrap yfg-next-inner\"><div><h2>Need to implement these steps into the actual project?<\/h2><p>Explain the type of website, target users, existing accounts and estimated launch time, and we will help organize the scope of implementation.<\/p><\/div><a href=\"https:\/\/yanxu.guilinkeji.com\/en\/about-us\/#contact\">Send Project Requirements<\/a><\/div><\/footer><\/article>","protected":false},"excerpt":{"rendered":"<p>Explain the purpose of A, CNAME, MX, TXT, NS and other records, and explain the correct methods for HTTPS, mail verification, CDN, resolution, and migration switching.<\/p>","protected":false},"author":1,"featured_media":2575,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[93],"tags":[127,128,113],"class_list":["post-2686","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technical-capabilities","tag-dns","tag-https","tag-server-deployment"],"_links":{"self":[{"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/posts\/2686","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/comments?post=2686"}],"version-history":[{"count":1,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/posts\/2686\/revisions"}],"predecessor-version":[{"id":2694,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/posts\/2686\/revisions\/2694"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/media\/2575"}],"wp:attachment":[{"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/media?parent=2686"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/categories?post=2686"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/yanxu.guilinkeji.com\/en\/wp-json\/wp\/v2\/tags?post=2686"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}