Why Multiple IP Addresses Are Required When I Create a Dedicated Load Balancer?
These IP addresses are used by underlying resources.
Generally, 2 IP addresses are required for creating a load balancer in an AZ, and 6 IP addresses are required for creating a load balancer with IP as a Backend enabled. If you create a load balancer in multiple AZs, more IP addresses will be required. There is an algorithm to determine how many IP addresses are required.
Parent topic: Load Balancers