What does DNS propagation mean?
Whether you manage your own website or have a team of professionals manage your site, you may have run across the term “nameserver”, aka DNS. However, you might not have any real understanding of what one is or how it works. As it turns out, knowing a little about this concept can come in handy for managing your site.
Put simply, a nameserver helps browsers make connections between URLs (Uniform resource locator) and websites. They’re incredibly important, as, without them, we would have to memorize IP addresses in order to access websites.
When you update the nameservers for a domain it can take up to 24-48 hours for the changes to take effect or propagate. This lifeless dead period where you cannot get to your website is called DNS propagation.
In other words, it is a period of time the ISP (Internet service provider) nodes across the world take to update their caches with the new DNS information of your domain.
Due to DNS caches of different levels, after the nameservers change, some of your visitors might still be directed to your old server for some time, whereas others can see the website from the new server shortly after the change.
Kinsta.com has a full-blown article regarding DNS and NameServers here!