Question

If I know that clients connecting to my EC2 instances will always have the same static IPs, is it possible to configure the EC2 elastic load balancer to redirect specific clients (based on their IP) to specific instances?

So:

123.22.31.11 ----> always goes to instance A
123.22.31.12 ----> always goes to instance B
123.22.31.13 ----> always goes to instance C

Answer 1

There are some interesting things you can do with ELBs in combination with latency-based Route 53 DNS records, but as far as I know there’s no way to load balance based on incoming IPs.

Some relevant documentation:

http://docs.amazonwebservices.com/ElasticLoadBalancing/latest/DeveloperGuide/using-domain-names-with-elb.html

http://docs.amazonwebservices.com/Route53/latest/DeveloperGuide/CreatingLatencyRRSets.html

http://docs.amazonwebservices.com/Route53/latest/DeveloperGuide/HowToLatencyRRS.html