How can I define a maximum number of instances to start?

The maximum number of instances that will be started by load based auto scaling is the number of load based instances in the given role. The instances will be started in batches.

number_of_load_based_instances.png

If you create two load based auto scaling instances, only up to two instances will be started by load based auto scaling. If you have no load based instances, none will be started.

The minimum number of running instances is the number of normal '24x7' instances that you manually started.