To inexperienced users, the Domain Name System (DNS) can seem very complicated.
While it can in some cases be complex, DNS problems can be easily diagnosed once you understand the basic core ideas behind it.
What is DNS?
DNS or domain name system is the protocol on the internet that turns human-comprehensible domain names such as cnn.com or guardian.com into addresses understandable by machines like 105.26.117.8.
DNS can be considered something similar to a phone book.
When you move from one location to another, your name stays the same, but your phone number may change.
In order to point your name to the new phone number, you must contact the telephone service provider so that they assign you the new phone number and update all directory information to reflect you as pointing to this new phone number.
In this way, the IP address can be compared to a phone number: When someone calls http://www.example.com/, your ISP looks at the DNS server and asks “how do I contact example.com?”
The DNS server responds: “It can be found at 198.105.232.4?.
What is a name server, a DNS zone and DNS records?
A nameserver is a computer that is permanently connected to the internet and translates domain names into IP addresses (or vice versa), enabling you to use www.example.com instead of 105.26.117.8.
When registering a domain name, you will need nameservers configured to handle requests for your domain names.
They keep record of your domain name’s DNS entries.
Domain Name System (DNS) allows a DNS namespace to be divided up into zones, which store name information about one or more DNS domains.
For each DNS domain name included in a zone, the zone becomes the authoritative source for information about that domain.
A DNS zone database is made up of a collection of resource records.
Each resource record specifies information about a particular object.
The DNS server uses these records to answer queries for hosts in its zone.
For example, address mapping (A) record, map a hostname to an IP address, and an MX record or mail exchange record maps a domain name to a list of mail exchange servers for that domain.
How does DNS do its job?
The DNS process could be explained in these few steps:
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You purchase a domain name with us and use our name servers.
- We let the internet know what nameservers have your domain’s DNS.
- The nameservers host your domain’s DNS. When someone wants to connect to your domain name the nameservers turn the domain name into an IP address and send the result to the visitor’s computer.
- The visitor’s computer receives the IP address answer from the nameservers and opens a connection to the web server at that address, requesting the web page.
- The web server responds and fulfills the request, transmitting the web page to the visitor’s computer.
This process is the same for other types of DNS records.