Hey,👋 In This article now, going to talk about what is DNS ? how to work? all details focused on DNS in this article. if it helps you, share it with others.
What is DNS?
DNS, or the Domain Name System, translates human-readable domain names (for example, www.amazon.com) to convert machine-readable IP addresses (for example, 192.0.2.44).
Computers can only understand numbers. We can’t remember the IP address. It is difficult for humans to remember the IP address so human-readable domain names are used in place of it.
In our routine life..you are visiting a different site like Google.com or Facebook.com, right? we have to remember only domain names in this..we don’t want to remember anything else.
For Example,
If we want to contact someone..we can search the name and we’ll do whatever we want...we don’t want to remember the number..we have to memorize only the name…like that in DNS, we have to remember only the websites name like facebook.com..we don’t want to remember numbers..in this way the DNS works.?
DNS Configure Types :
The first step in this process is when you search www.exmaple.com it will go to the actual DNS resolver in which settings default in your own computer.
If your search any website through an internet connection..every computer already has a default one DNS.
DNS has two options to configure to own computer:
- ISP Provides though DNS resolver
- You Set Manually Provide a DNS resolver
Public DNS and Private DNS
- Public DNS: For a server to be accessible on the public internet, it needs a public DNS record, and its IP address needs to be reachable on the internet.
- Best Free & Public DNS Servers (Valid June 2021)
- Google: 8.8. 8.8 & 8.8. 4.4.
- Quad9: 9.9. 9.9 & 149.112. 112.112.
- OpenDNS: 208.67. 222.222 & 208.67. 220.220.
- Cloudflare: 1.1. 1.1 & 1.0. 0.1.
- CleanBrowsing: 185.228. 168.9 & 185.228. 169.9.
- Alternate DNS: 76.76. 19.19 & 76.223. 122.150.
- AdGuard DNS: 94.140. 14.14 & 94.140.
Some Details:
So, let’s look at a very common DNS which is 1.1.1.1 this is basically a Cloudflare DNS IP address, and a lot of computers are configured.
Most DNS servers do not have an HTTP website for example this 8.8.8.8 is public DNS from google.
- Private DNS: Computers that live behind a firewall or on an internal network use a private DNS record so that local computers can identify them by name. Outside users on the internet will not have direct access to those computers.
How does DNS Work?
when you wrote example.com on any web browser first my HTTP request on My Operating System(os) IP address=>192.192,.193.194 go to my configured DNS server.
The Four DNS Servers that Load a Webpage
- DNS resolver: The DNS resolver is the server that responds to a DNS query and asks another DNS server for the address, or already has the IP address for the site saved.
- Root name server: A root name server is the name server for the root zone. It responds to direct requests and can return a list of authoritative name servers for the corresponding top-level domain.
- TLD name server: The top-level domain server (TLD) is one of the high-level DNS servers on the internet. When you search for www.example.com, a TLD server for the ‘.com’ will respond first, then DNS will search for ‘example.’
- Authoritative name server: The authoritative name server is the final stop for a DNS query. The authoritative name server has the DNS record for the request.
- More information in below
How to processed it?
1) My system IP address =>192.192,.193.194(client)
2) 192.192.193.194 (client) => hey ! ask my own DNS(Cloudflare). what is the IP address on www.exmple.com?
- The browser checks its cache and the computer’s cache for the DNS records that match the domain name we entered. If it succeeds, it requests the page from the website’s host.
- If we haven’t found our record yet, our request goes to our Recursive DNS Servers or Cloudflare DNS that we have set for our computer or network (probably our ISP). If they have the record cached, we take the results from them and try to load the page (and we also cache it locally for later use).
3) If we still haven’t found it 1.1.1.1 (Cloudflare DNS) => I don’t know, but I know a guy who knows?
4) 192.192,.193.194(client)=> hmm… okay I will wait.
5) 1.1.1.1(Cloudflare DNS) => 65.24.67.23( Root Name server): ask them where to find the .com domain website name, do you know?
6) 65.24.67.23 (Root Name serve): yes I know, you ask them 77.22.11.3(TLD Name Server)
7) 1.1.1.1(Cloudflare DNS) => 77.22.11.3(TLD Name Server): Hey ! do you have example.com IP address?
8) 77.22.11.3 (TLD Name Server): NO, but I know the guy, they are kept up to date on which Authoritative Name Servers(44.54.34.54) are responsible for example.com and they share that information with us. so you ask them Authoritative Name Servers(44.54.34.54)
9) 1.1.1.1 (Cloudflare DNS) => 44.54.34.54(Authoritative Name Server) : hey! do you have example.com IP address?
10) 44.54.34.54 (Authoritative Name Server) => yes, I know this is an example.com IP address 104.28.4.100.
11) 1.1.1.1(Cloudflare DNS)=> this example.com => 104.28.4.100
12) client: okay.
What are DNS Cache + Caching Functions?
DNS cache is a repository of domain names and IP addresses that are stored on a computer, so it doesn’t have to ask for the IP address every time. Imagine if any user tried to go to www.example.com DNS to query the authoritative name server example. The traffic would be overwhelming! The very thought of that much traffic is why we have DNS caching. DNS caching has two major goals:
- Speed up DNS requests
- Reduce bandwidth of DNS requests across the internet
The DNS cache methodology does have some issues, however:
- it could be a while before every DNS server has its cache updated to the latest IP data
- DNS cache is a potential attack vector for hackers
There are a few different types of DNS caching used on the internet:
- Browser DNS caching: Current browsers circa 2018 have built-in DNS caching functionality. Resolving a DNS with the local cache is fast and efficient.
- Operating System (OS) DNS caching: Your computer is a DNS client, and there is a service on your computer that manages DNS resolution and requests. This DNS cache is also local and therefore fast and requires no bandwidth.
- Recursive resolving DNS caching: Each DNS precursor has a DNS cache, and it stores any IP address that it knows to use for the next request
Most FAQ asked Question
1) Best Domain Name Registration Sites Of June 2021 ·
- BlueHost
- Hostinger ·
- GoDaddy
- . BigRock
- HostGator
- Scala hosting.
2) Is it safe to clear the DNS cache on the DNS server?
It’s important to flush a DNS cache for a few reasons. The first is the cache may contain outdated information. You might experience this as difficulty accessing websites or applications. If the domain name in the cache points to an old or incorrect IP address, the website won’t return the correct information.
3) How long do DNS records take to update?
72 hours. DNS propagation is the time frame it takes for DNS changes to be updated across the Internet. A change to a DNS record — for example, changing the IP address defined for a specific hostname — can take up to 72 hours to propagate worldwide, although it typically takes a few hours.
Note:
DNS propagation is the time frame it takes for DNS changes to be updated across the Internet
4) How long does it take for a domain to become active GoDaddy?
about 24–48 hours. It usually takes about 24–48 hours before it is visible to all users of the Internet. Sometimes propagation delays due to Internet providers have to update their records (DNS tables) to reflect the changes.
Note:
DNS propagation is the time frame it takes for DNS changes to be updated across the Internet