Here are some examples
Windows 2000, XP, Vista, Windows 7, Windows 8, Linux, iOS, Android all behave differently
Examples of well known hosts which have low DNS TTL values (0-60 s) and other examples of funny DNS configurations
A recommended TTL value for and A record is usually between 30 and 60 minutes (, ). Short TTLs (30s - 5m) are used for Failover, Load Balancing or DDOS mitigation. There are some hosts with very short TTLs (20-30s) and even 0s (no caching at all!)!
In most cases overriding minimal TTL for Web site and setting it to 120-300s doesn't have any negative impact.
Follow these easy steps to avoid performance degradation caused by slow DNS lookup
Conditional DNS resolution, DNS pre-resolving, monitoring and other best practices
List of DNS timeouts for your reference
The last release of Namebench, the DNS Benchmark, dated Jun 2010. Learn how to modify Namebench for your need to get correct resutls
.test .example .localhost .invalid wikipedia