Create a dynamic scaling policy

You will use the previously created alarm to create a dynamic scaling policy which will be attached to the Auto Scaling Group.

1. Go to EC2 console > Auto Scaling > Auto Scaling Groups.
2. Select the group Talend ESB Auto Scaling group.
3. Click Scaling Policies panel.
   There is no scaling policy displayed in this panel since no dynamic scaling policy is defined yet for your Auto Scaling group.

   

4. Click Add policy > Create Alarm. Then use the following information:

   Field	Value
   Name	Scale up on HighRequestCount
   Execute Policy when	Select HighRequestCountAlarm in the drop-drown list.
   Take the action	Add 2 instances when 60 <= RequestCount < +infinity
   Instances need	300 seconds to warm up after each step.

   

5. Click Create.

   The dynamic scaling policy is created and fully configured. You can test it by generating a large amount of traffic through the load-balancer endpoint using tools like SoapUI or Apache JMeter.

   As soon as the Request count is higher than 60 (or any other value that you defined) during 2 minutes, AWS will automatically add two more instances to the Auto Scaling Group.