How to register new EC2 instance under Elastic Load Balancer ELB

Follow these steps to register EC2 Instance under ELB:

From the Main Menu, select Elastic Load Balancer.

Under the ELB table from the menu, select Register Instance.

In the new window, select the Instance or multiple Instances you want to attach to the given ELB. To select multiple Instances, press and hold Ctrl key.

Click Register.