Before using Server Load Balancer, you have to create two ECS instances at least and build corresponding applications on them. Then, add them to the Server Load Balancer instance to process the distributed client requests.
Follow the instructions in this document to create two ECS instances, ECS01 and ECS02.
Log on to the ECS console.
In the left-side navigation pane, click Instances and then click Create Instance.
On the buy page, configure the ECS instance.
The following are the ECS settings used in this tutorial. For more details，refer to Create Linux ECS instances.
Region：In this tutorial, select China East 1.
Note: Because Server Load Balancer does not support cross-region deployment. the region of the Server Load Balancer instance and the ECS instance must be the same.
Network Type：In this tutorial, select VPC. Use the default VPC and VSwitch.
Operating System：In this tutorial, select Ubuntu 16.04 64 bit.
Number of Instances：In this tutorial, select 2. The system will create two ECS instances with the same settings at one time.
Click Buy Now and complete payment.
Go back to the ECS Instance List page and click China East 1.
Move the mouse pointer over the instance name and click the displayed pencil icon to change the instance name to ECS01 and ECS02 separately.