Lowering DNS TTL Will Not Speed Up Failover
Reducing DNS TTL does not speed up failover. Discover the findings from a study on detection and propagation times in DNS settings.
A three-month study revealed that reducing DNS TTL does not speed up failover times as commonly believed. Experiments during an AWS outage showed that failover comprises two main components: detection time and propagation time. While detection time remained constant across TTL settings, propagation time varied significantly depending on the resolver. This insight challenges conventional wisdom about DNS configuration for cloud failover.