Balancing work load in multiple Availability Zones can be performed in two separate ways: Using Cross Zone or without Cross Zone balancing.  Cross Zone Load Balancing will divide up the traffic by the number of instances targets, regardless of the zone they are located in. Without cross zone load balancing each zone receives the same amount of requests.

Cross-Zone load balancing characteristics:

        1.  Application Load Balancing

                a.  Enabled by default.

                b.  No charges for inter AZ data transfer.

        2.  Network and Gateway Load Balancing

                a.  Disabled by default.

                b.  You are charge for inter AZ data transfer.

        3.  Classic Load Balancer

                a.  Disabled by default.

                b.  No charges for inter AZ data transfer.

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1.  Logon to AWS as an IAM user at URL:  https://signin.aws.amazon.com/

2.  From the Home Console type EC2 in the search bar, select the star next to EC2, and select EC2

3.  On the left hand menu bar select Load Balancer

4.  At the load balancer page, select your load balancer ? Actions ? Edit load balancer attributes.

5.  Under Availability Zone routing is the option to enable and disable.