The DNS System
The Domain Name Server (DNS) system is a global infrastructure that enables translating human-readable domain names such as “www.yourdomain.com” into Internet Protocol (IP) addresses such as “184.108.40.206”.
When a browser or device needs to discover the IP for a hostname, it begins a DNS lookup process. It consults a DNS server, and may be referred to several other DNS servers, until it reaches the authoritative name server that holds the IP address and other details for the required hostname. At each stage in the DNS query process, systems can store DNS information in their local cache.
What is DNS propagation?
DNS propagation is the time DNS records take to update in order to be in full effect across all servers on the web. Changes aren’t instantaneous because of the stored record information in the nameserver’s cache, and it will stay like that until they refresh. While your domain won’t experience any downtime from properly planned record changes, some users will still be served a cached version of your site until all servers have propagated.
How long does it take to propagate?
It can take anywhere from a few to 72 hours. This timeframe depends on multiple factors, including the domain’s registry, ISPs (Internet service providers) and the TTL values on the DNS records.