DNS propagation does not exist

A widespread fallacy among IT professionals is that DNS propagates through some network. So widespread in fact, that there are a couple of sites dedicated to visualizing the geographic propagation of DNS records. But DNS propagation does not exist.

Sites that capitalize on a common misconception

So how _does_ it work?

When you request DNS records from the server that is authoritative for that domain (i.e. who “owns” it), it will accompany those records with a TTL (time to live). This indicates how long you can keep using those values before you should request a fresh copy. The records are stored in a cache on your device. Eliminating the need to query the DNS server every time speeds things up and offloads the DNS servers.

A suggested change in terminology

Okay, so “DNS propagation” may not be the best choice of words. But why does that matter?

Data engineer at BigData Republic

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