When updating your DNS or changing your nameservers, there is always propagation time. To elaborate, propagation time is the amount of time it takes for your update to take effect across the entire Internet.
The typical propagation time for a nameserver change ranges from 24-48 hours. In contrast, if your domain name is already using our nameservers, any changes to your DNS typically propagate in 30 minutes.
Why the delay? DNS records are stored in a cache and that cache has a refresh rate -- also known as the TTL or Time to Live. This setting communicates to the DNS resolver the length of time it needs to cache a DNS query before inquiring for a new one.
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