Domain name owners know that acquiring a domain comes with extensive learning about DNS. One of the most important terms you will learn as a result of purchasing your domain will be “propagation.”
Propagation, such a simple word that hides a heavy concept and often several questions. What is it, why is it necessary, how long can it take: these are all questions I have asked myself when I first entered the world of web hosting.
To give you a head start, let me walk you through what I’ve learned about propagation.
What is Propagation?
Propagation is self-explanatory. It represents the time needed for changes to a domain name to be visible around the world. Since the Internet is large and vast, it can take up to 48 hours for the changes to be completed.
For example, if you move your site to a new host, you will necessarily have to update your domain. Then you will have to wait for the change to finish propagating so that everyone can see the site on the new server.
How Does Propagation Work?
Much of the Internet is automated on mega servers called “Root Nameservers“. It’s thanks to cache they store in their memory that the Internet is so fast (or slow when we talk about propagation).
The cache temporarily stores domain name information. This prevents redundant requests to external servers and makes the web experience smoother and faster for everyone. So, the changes you made will not be visible until the cache is updated on the root servers.
The server cache is not constantly emptied as each server operates on a different schedule. Therefore, it may take 4 to 48 hours before the entire planet can see your modifications. Fortunately, these servers are all interconnected. Thus, when it is up to the next one to update, it will quickly find the new information on the previous server.
It’s a bit like playing the telephone game. The first server tells the 2nd what it heard, the 2nd repeats it to the 3rd server, and so on until all servers have been updated. Unlike the real game, this exchange of information is accurate!
Who Determines the Propagation Time?
No one determines the propagation time; this is only determined by the schedules programmed in each of the root servers. It is therefore almost impossible to know when a root server will update its cache memory. However, in the majority of cases, it rarely exceeds 48 hours (or 2 days).
Of course, some hosts and webmasters have ways of partially bypassing the propagation process or even accelerating it. These techniques attempt to change the frequency at which a root server updates its cache. However, be aware that even these techniques do not guarantee immediate changes.
We cannot control DNS propagation. No matter which modification you would like to make, it is possible that you must wait a few hours afterwards.
The best resources available to you are your web hoster, as well as sites that verify the status of your DNS propagation like whatsmydns.net.
If you need to see your site during the propagation period, check out our article on how to modify your “hosts” file. If you have any other issues, you can always write us a ticket, we will be happy to offer you our assistance with your modifications.