Auto Scaling is free of charge. However, you must pay for the resources of other Alibaba Cloud services used in Auto Scaling, such as Elastic Compute Service (ECS), Server Load Balancer (SLB), and ApsaraDB RDS instances.
ECS instances in scaling groups are categorized into the following types:
- Existing ECS instances that are manually added to a scaling group. The subscription, pay-as-you-go, and preemptible instance billing methods are supported.
- ECS instances that are automatically created during a scale-out event. Only the pay-as-you-go and preemptible instance billing methods are supported.
The following table describes the ECS instance resources for which you must pay. ① indicates a billing method that offers discounts to reduce the costs of pay-as-you-go resources. You can purchase pay-as-you-go resources. For more information, see Billing overview.
|Computing resource (vCPUs and memory)||You are charged based on the instance type that you choose. The instance type determines the number of vCPUs and the size of memory that you can use.||
|Image||The image fees are determined based on the image type and your usage.||
|Disk||The disk fees are determined based on the disk capacity and duration of use.||
|Snapshot||The snapshot fees are determined based on the snapshot size and storage duration.||
|Public bandwidth||If you use a public IP address to access the Internet, you are charged only for the outbound public bandwidth.||
The following table describes the billing methods of ECS instances in different states. For more information, see No Fees for Stopped Instances (VPC-Connected).
|Billing method of ECS instances||ECS instance state||Billing of additional ECS resources|
|Subscription||Running||You are charged for the additional ECS resources such as images, disks, public bandwidth, and snapshots based on their individual billing methods.|
|Stopped||You are charged for the additional ECS resources such as images, disks, public bandwidth, and snapshots based on their individual billing methods.|
|Pay-as-you-go (including preemptible instances)||Running||You are charged for the additional ECS resources such as images, disks, public bandwidth, and snapshots based on their individual billing methods.|
Other Alibaba Cloud services
Auto Scaling does not create resources listed in the following table. Auto Scaling must associate scaling groups with these resources during the usage. You must create and pay for these resources in advance by using the consoles of other Alibaba Cloud services or by calling API operations of other Alibaba Cloud services.
|Server Load Balancer (SLB)||If you want to associate a scaling group with SLB instances, you must create and pay for the SLB instances in advance.||Pay-as-you-go|
|RDS||If you want to associate a scaling group with RDS instances, you must create and pay for the RDS instances in advance.||Pricing, billable items, and billing methods|