How to control traffic using Weighted Records DNS Policy?
Weighted records distribute traffic among different resources without using a load balancer. Instead of having one active record and one passive record (failover records), keep all the weighted records active simultaneously. Consider, there are four records for www.example.host. The policy for each of these is weighted and each resource record points to a different target, web1-east, web2-east, and so on. In contrast to the failover records where Route 53 serves only the primary record, weighted records are always active. That means if a client tries to resolve www.example.host, Route 53 may respond with any one of the web instance IP addresses. Which specific IP address Route 53 responds with is determined by the record weights. In the routing policy column, the weight of each record is specified. After adding up all these values, the count is 100. Consider each record has a value of 25, which means each record has a 25% chance of getting selected. In other words, which record Route 53 serves up is random, and the idea is to distribute traffic across multiple instances, and by adjusting the weighs traffic is controlled which each target receives.