If you have a website or are interested in starting one, you’ll likely ask yourself “What is domain propagation?” at some point. Simply put, it’s the process of updating every server on the Internet current with new information.
Also known as DNS propagation, any changes made to your domain name, name servers, or IP address will involve DNS propagation. This process can take up to 72 hours to fully propagate.
To completely understand the process of how domain propagation works, and the time it takes, you need to understand how DNS servers work and how they are updated.
How Do DNS Servers Work?
DNS servers carry out the job of interpreting domain names into IP addresses. As far as you and your website visitors are concerned, your website is situated at an easy-to-remember name such as www.yoursite.com, but it’s really situated at a less simple-to-recall IP address like 123.456.789.101.
Every time you enter a website name, a DNS server takes that name and processes which numerical location it has to send you to the correct spot. It’s a procedure that works reasonably fast and flawlessly, which implies more often than not, you don’t need to worry, or even think about it.
The only time you have to consider it is when you make a DNS change.
What Happens If You Make a DNS Change?
If you change your hosting provider or alter your domain name, every single DNS server has to receive that updated information and register it before they can convert your domain name to the correct IP address.
Complicating the process, different servers will get the updated data at different times, making domain propagation times sporadic. It’s possible for you to type the updated website name and see the new site almost immediately while someone across town will see the outdated one.
Since DNS changes are not that common, most servers retain the information gathered in prior searches in their cache memory. This means that if someone searched for your website last week and the DNS server successfully translated the domain to an IP address, then it will do the exact same thing.
Eventually, over the next few hours (up to 72 hours), the servers will notice the change has been made and update accordingly, the will redirect visitors to the new IP address where your website is now located.
DNS propagation may sound a bit confusing, but the problem is only a temporary one. Over the next couple of days, every DNS server in the world will receive the information and propagate the update.
Why Is DNS Important?
The Domain Name System, (DNS) is the very foundation on which the Internet stands and operates.
When you type in a website address into your browser window, like www.mywebsite.com, your computer will make contact with a DNS server to decipher the IP address of that website’s server.
Once the correct IP address has been found, the website’s server will display the correct pages on your computer screen. This process is known as Domain Name Resolution.
The DNS is a database of website domains and IP addresses. Its principal function is to store the data and connect the two pieces of information. However, these records are stored in a huge network of connected servers each one only handling a relatively small amount of data.
With such a vast network of servers storing the data for every website and IP address, the time to propagate any changes to a domain can vary dramatically.
How Long Does Propagation Take?
Whenever any changes are made to the nameservers of your domain, moving the domain from one hosting company to another, or change from one server to another, the time for the propagation to complete depends on a number of things…
The Time to Live (TTL) setting in your DNS record is the time, in seconds, that servers remember DNS data before it expires and a replacement query must be performed.
Every record within the name zone file can have the TTL setting individually set. The shorter the TTL time, the quicker the propagation speed, however, this will conjointly result in slower server process times.
The default setting for many DNS records is 86400 or twenty-four hours, before Time to Live. This, however, can be modified.
If you set the TTL to one hour for a particular record, servers will store the information for that record for that amount of your time before obtaining the new data.
Your ISP (Internet Service Provider)
Some ISPs, rather than updating the DNS information as it happens, will store data in an attempt to speed up Internet traffic.
Your ISP may even ignore any changes you have made to the TTL settings, refreshing their system every couple of days or so.
Your Domain Name’s Registry
If you make changes to your domain name’s nameservers, that information is sent to the domain registry within minutes of the request, and they, in turn, publish the updated DNS records.
Nearly all registries perform updates without delay. However, some protect their systems from overload by setting a high TTL in excess of 48 hours.
It is also worth noting that browsers will frequently cache specific website information so as to give faster loading times on subsequent visits.
Once the propagation has been completed, users may still need to refresh the page or clear their browser’s cache to view the correct site.