Technology is the keystone of modern life. It has made many things easier! It has also accelerated many processes and daily tasks to the point we humans now expect everything to happen at light speed. Today, waiting three seconds can be a reason to abandon a web search or a website because that feels “too long”.
The reality is, massive processes, even with advanced technology involved, still, require much more than milliseconds to be completed accurately. Like DNS propagation!
What’s DNS propagation?
DNS propagation is the time period that it takes to update DNS modifications across the Internet.
Why should I need to modify DNS records?
The regular maintenance of your network or online business demands DNS modifications. Of course, the amount and frequency differ based on the kind of business. But to add, edit or remove DNS records is a common task for administrators. Every time they have to route the e-mail, redirect visitors to any subdomain, modify IP addresses, TTL (time-to-live) values, etc.
How does DNS propagation work?
When you modify a DNS record (or more), you have to make it on the authoritative DNS nameserver. But a network includes not only a server but many of them to comply with different functions. So your modifications got saved in the authoritative nameserver, but there are many recursive servers distributed globally that have to be updated. Otherwise, they will keep serving the previous copy (outdated) of the DNS records. Remember, all recursive servers save a copy of the DNS records within their cache memory.
Clearly, the goal is for the new update to be available worldwide. Until DNS propagation gets completed, the goal will be achieved.
How long does it take for DNS propagation to be completed?
Usually, DNS propagation takes from 24 hours to 72 hours to be completed. This is an approximate time, but it can take less or even more! Basically, because there are extra factors that can make this process faster or slower. In any case, you can be sure that this is not about milliseconds. Better be patient!
Which factors can affect DNS propagation?
- DNS modifications on a high DNS level (hierarchy) take longer.
The TTL for TLD and root servers is usually defined with higher values, 48 hours, or even more. This is a common practice used to avoid stress on these servers due to high demand.
For instance, if you change the authoritative nameserver of your domain, meaning the server with your original DNS data, this is not a minor modification. You must change it on the TLD level by communicating with the domain registrar. DNS propagation of such a change will definitely take longer.
- TTL of the DNS records.
Recursive servers keep a copy of the DNS records, the time the TTL set on those records allows. Until the TTL expires, recursive servers will keep the old copy. Therefore, full DNS propagation depends on those TTLs.
- TTL of the ISPs’ servers.
For Internet service providers to set higher values (TTL) on their servers is convenient. They can make the traffic more agile and optimize their resources. This can delay the DNS propagation until the TTL on the ISP servers expire.
- DNS cache on users’ devices.
Devices save (cache) DNS records of the websites accessed by the user. This information remains cached for the time defined by the TTL. An update could happen after the records expire.
Understanding DNS propagation is vital to know how to influence this process in your favor. With the fast pace technology advance, one day, this will happen quicker. But meanwhile, be patient!