DNS is the internet's phone book: you type a memorable domain into your browser, and DNS translates it into the server's real numeric address so visitors can find your website. The DNS records are the different entries in that phone book where your domain's information is listed. Understanding this makes sense of why "a DNS change takes a while to take effect," and lets you tell your provider which record to check when the website or email misbehaves.
Who should read this? ❓
If you have a website or company email and have ever run into any of these, this is worth reading: the site wouldn't update after a host change, email suddenly stopped arriving, or someone asked you to "add a DNS record" and you had no idea what that meant. If none of that applies and you don't expect it to, skip this one.
First, why DNS exists at all
Every server on the internet is really identified by a string of numbers (an IP address, like 142.250.x.x). But nobody can remember a long string of digits, let alone print it on a business card. A domain exists so people can use a memorable name; and DNS (the Domain Name System) is the phone book in the middle that translates between "name" and "number". You type the domain, DNS looks up the matching server address, and your browser can connect.
Inside that phone book, the different pieces of information about your domain are filed under different "records". There are only a handful of common ones, and each exists to solve one specific problem.
The most common DNS records, and the problem each solves
- A record: points your domain at the website server's real numeric address. "Changed servers but the site still loads the old one" is usually about this.
- CNAME record: forwards one name to another, so that, say, the www and non-www versions of your address both reach the same website.
- MX record: tells the world which mail server should receive email sent to @yourcompany.com. If email isn't arriving, check this first.
- TXT record: a "notice board" used to prove the domain is yours and to hold email-security rules (SPF, DKIM, DMARC).
- NS (name server) record: decides which "phone-book company" manages all the records for your domain.
Why "a DNS change takes a while"
This is the single most common point of confusion. To keep access fast worldwide, DNS answers are temporarily cached at servers everywhere for a set time (called the TTL). When you change a record, the old answer still sits in caches around the world; the new setting takes effect region by region only as those caches expire, which can be anywhere from a few minutes to many hours. So when nothing changes immediately after a DNS edit, it's usually not a mistake — it's the caches catching up. It's also why moving a server or switching email service is best planned ahead and timed carefully rather than done on the fly.
How 5U Website manages DNS for clients
DNS configuration is the kind of thing nobody notices when it's right and that takes down a whole site, or a whole company's email, when it's wrong. Over the years we've handled a great many migrations, mail-service switches, and domain transfers across registrars and DNS hosts like GoDaddy and Cloudflare. We recommend keeping a business's DNS under one provider it genuinely controls, rather than scattered across whoever set up each piece. Our approach: before touching any record, document the current state, assess the TTL and the blast radius, and where needed make the change in stages — heading off the "website loads but email won't arrive" kind of split before it happens.
Let us handle it
You don't need to work out how each record should be filled in; that's our day-to-day work. 5U Website's website design, development and hosting service includes DNS configuration and maintenance. If your website or email is behaving erratically or a change "won't take effect", send us an email; we typically get back to you within a business day or two.
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