How to configure AWS ELB to block certain IP addresses? (known spammers) [closed]

Answer 1

You can't do this from an ELB that is not instantiated inside a VPC (at the date of this answer). If inside a VPC, check out the other answers. If not, you can switch to something more controlable, such as HAProxy or place CloudFlare (https://www.cloudflare.com/) in front of your ELB, which is probably a better option.

Answer 2

I would try using VPC ACLs for that. First of all, ELBs inside VPC can use Security Groups but they only specify a traffic you allow in and out of an ELB. To actually block a traffic coming from a certain IP - an ACL would be the best.

For that to work - a pair of a public (internet-facing) and internal ELBs need to be used with internal ELB protected by subnet ACL DENY rules.