DNS Là Gì?
You may have heard of DNS, or Domain Name System, when you registered your domain or built a website. But what exactly is DNS, and why is it so important? DNS powers the internet by converting alphabetic names into numeric IP addresses—it makes it so you only need to remember a domain name, like coolexample.com, instead of a numeric IP address. DNS is the backbone of the internet, and without DNS, you wouldn't be able to send an email, scroll through Instagram, or play video games with friends.
So, what is DNS and why is it important?
Back in the old days when you wanted to call someone, you had to memorize their phone number, keep track of their number in a notebook or rolodex, or look it up in the giant paper phonebook. Today, our cell phones can store those phone numbers in the contacts list, and each number is mapped to a specific person or business. When you want to call your friend Jane, you don't have to remember her phone number—you just need to find her name in your contacts list and place the call.
You can think of DNS as the contacts list of the internet, but instead of mapping people to phone numbers, it maps domain names to IP addresses. And IP addresses are the language of the internet. Computers communicate with each other using Internet Protocol, or IP addresses, which are specific sets of numbers and letters, such as 126.96.36.199 (an IPv4 address) or 2001:0db8:85a3:0000:0000:6a2e:0371:7234 (an IPv6 address).
But those long strings of numbers and letters aren't very easy to remember. So, DNS maps IP addresses to human-friendly domain names, like coolexample.com. Remembering a domain name is usually a lot easier than keeping track of all those IP addresses, making it more enjoyable to surf the web.
Okay, but how does DNS really work?
You may have heard the phrase DNS query or DNS lookup when searching for info on DNS. These are common ways to reference how DNS works and gets you to a particular website. But there are a few steps along the way, so we'll break those out and describe each step. Heads up—we're about to get a bit technical.
- The query: It all starts when you type a domain name, like coolexample.com, in the address bar of your web browser. After entering a domain, a query begins looking for the IP address of coolexample.com so your browser can display the correct content. The query starts by checking the root server to see where to go next.
- The root servers: There are 13 root servers working across the world, and they know all the DNS information of all domains. The root server looks through that DNS info to determine where to look next: the TLD nameserver.
- TLD nameservers: The TLD, or top-level domain, is the last part of a domain name, such as .com in coolexample.com. Some of the most common TLDs are .com, .net, and .org, and some of the most popular country-specific TLDs are .uk, .ca, and .au. All TLDs have a specific TLD nameserver that stores the DNS info for that specific TLD. So, if I want to visit coolexample.com, the original query needs to check the .com TLD nameservers to find the domain nameservers for coolexample.com.
- The domain nameserver: This is where you'll find the DNS zone file for coolexample.com, and the zone file is where you'll find individual DNS records. These records, such as A records, MX records, and subdomains, can be added, edited, or deleted in the zone file. The original query will look in the domain nameserver to find the A record for coolexample.com, which is mapped to a specific IP address. This IP address is what our query will use to retrieve and display the website content for coolexample.com in your web browser.
Keep in mind that there are a few different stops DNS can take along the way, and sometimes things get stuck or don't work like we expect. And it can take up to 48 hours for DNS changes to show up on the internet globally. If you'd like more detail about how DNS works, check out this handy guide from Verisign.
A little more about nameservers...
Have you ever heard someone mention "changing nameservers" for your domain? That's because the last step in the query is checking the domain nameservers for that all-important IP address. But you need to have the correct nameservers before the query can find the correct IP address.
There are always at least two nameservers for a domain, and when nameservers are changed, the place where you manage DNS also changes. For example, if the domain is using default GoDaddy nameservers, the DNS zone file will be in your GoDaddy account. But if the domain is using nameservers for a different company, the DNS zone file will be with that company instead.
What do I need to do with my DNS?
Now that you know a little about what DNS is and how it works, you're ready to start using DNS in your GoDaddy account. The easiest way to access your DNS is to sign in to your GoDaddy domain portfolio, click or tap directly on your domain name, then select Manage DNS. You should see your DNS zone file now, which is where you'll—you guessed it—manage DNS for that particular domain.
From here, you can take on some of the most common DNS tasks:
- Connect your domain to your website by editing your A record, the record that determines what happens when someone enters your domain in their web browser by mapping your domain to an IP address.
- If you already built a website somewhere else, or you'd like to connect your domain to your Twitter, YouTube, or TikTok account, then domain forwarding might be the best option.
- Make sure your emails get delivered to the right account with correct MX records.
- Creating a separate online store where folks can shop for your products? Add a subdomain that points to the IP address of your online store, or add a subdomain that points to another domain.
- And if you're setting up DNS somewhere else or using advanced DNS functions, change your nameservers to move your zone file to the other company.
Phần lớn cập nhật DNS có hiệu lực trong một giờ, nhưng có thể mất đến 48 giờ để cập nhật toàn bộ.
What if I get stuck?
We get it—there are a lot of moving parts to managing DNS for your domains, and it can get confusing. We've worked hard to create a seamless experience when managing DNS, and we're always working to improve. If you get stuck or have questions, we have help articles to walk you through DNS tasks, videos to explain different domain tasks, and our award-winning GoDaddy Guides are just a chat or call away.
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