How does DNS failover handle cached entries around the world? If my site fails over, will people who have been visiting my site still be able to using the new IP?
Dealing with DNS cache is challenging for a DNS failover service. Even when setting the TTL for your A record to a very low number, certain ISPs or networks will ignore those TTLs and elect to set the cache for a value that they deem appropriate. You can’t do much about this. The good news is that this really only affects a very small portion of the Internet and users who have previously cached your IP.
