Moves the specified instances into the standby state.
If you choose to decrement the desired capacity of the Auto Scaling
group, the instances can enter standby as long as the desired capacity
of the Auto Scaling group after the instances are placed into standby is
equal to or greater than the minimum capacity of the group.
If you choose not to decrement the desired capacity of the Auto Scaling
group, the Auto Scaling group launches new instances to replace the
instances on standby.
For more information, see Temporarily removing instances from your Auto Scaling group
in the Amazon EC2 Auto Scaling User Guide.