- What's New
- Function Overview
- Service Overview
- Getting Started
- User Guide
- Best Practices
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API Reference
- Before You Start
- API Overview
- Calling APIs
- Getting Started
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APIs
- AS Groups
- AS Configurations
- Instances
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AS Policies
- Creating an AS Policy
- Creating an AS Policy (V2)
- Modifying an AS Policy
- Modifying an AS Policy (V2)
- Querying AS Policies Bound to an AS Group
- Querying AS Policies Bound to a Scaling Resource (V2)
- Querying AS Policies (V2)
- Querying an AS Policy
- Querying an AS Policy (V2)
- Executing, Enabling, or Disabling an AS Policy
- Deleting an AS Policy
- Batch Managing AS Policies
- AS Policy Execution Logs
- Scaling Action Logs
- Quotas
- Notifications
- Lifecycle Hooks
- Tags
- API Version Query
- Application Examples
- Permissions Policies and Supported Actions
- Appendix
- Change History
- SDK Reference
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FAQs
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General
- What Are Restrictions on Using AS?
- Must I Use AS Together With ELB and Cloud Eye?
- Is AS Billed?
- Will an Abrupt Change in Monitoring Metric Values Trigger an Unnecessary Scaling Action?
- How Many AS Policies and AS Configurations Can I Create and Use?
- Can AS Automatically Scale Up or Down vCPUs, Memory, and Bandwidth of ECSs?
- What Is an AS Quota?
- How Do I Fix the Error "The key pair does not exist" When I Connect to an Instance?
- What Types of EIP and Shared Bandwidths Can Be Adjusted by AS?
- What Types of ECS and HECS Instances Can Be Scaled by AS?
- If the OS of an ECS Instance in an AS Group Is Upgraded, Can AS Automatically Add Instances with the Newest OS During the Next Scale-out Action?
- Can AS Add Yearly/Monthly ECS Instances When It Scales Out an AS Group?
- Can AS Increase Bandwidths as Required?
- AS Group
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AS Policy
- How Many AS Policies Can I Enable?
- What Are the Conditions to Trigger an Alarm-based AS Policy?
- What Is a Cooldown Period and Why Is It Required?
- Can AS Scale Capacity Based on Custom Monitoring by Cloud Eye?
- What Monitoring Metrics for an AS Group Will Be Affected If VM Tools Are Not Installed on the Instances in the Group?
- What Can I Do If an AS Policy Fails to Be Enabled?
- How Do I Install the Agent on Instances in an AS Group to Use Agent Monitoring Metrics?
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Instance
- How Do I Prevent Instances Manually Added to an AS Group from Being Automatically Removed?
- When an Instance Is Removed from an AS Group and Deleted, Is the Application Data Saved?
- Can I Add Yearly/Monthly ECS Instances to an AS Group?
- Can AS Automatically Delete Instances Added Based on an AS Policy When They Are Not Required?
- What Is the Expected Number of Instances?
- How Do I Delete an ECS Instance Created in a Scaling Action?
- Will ECS Instances Be Deleted If They Become Unhealthy?
- How Do I Handle Unhealthy Instances in an AS Group?
- Why Instances in an AS Group Keep Failing Health Checks and Getting Deleted and Recreated?
- How Do I Prevent Instances from Being Automatically Removed from an AS Group?
- Why Is an Instance that Was Removed from an AS Group and Deleted Still Displayed in the ECS List?
- Do I Need to Bind an EIP to an Instance Before I Manually Add the Instance to an AS Group?
- Can I Apply the Configurations of an Existing Instance in an AS Group to Instances to Be Added in the Future?
- Will the System Bind a New EIP or an Existing One a Newly Added ECS Instance?
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Others
- How Can I Automatically Deploy My Application on an Instance?
- How Does Cloud-Init Affect the AS Service?
- Why Can't I Use a Key File to Log In to an ECS?
- Do I Need to Configure an EIP in an AS Configuration When a Load Balancer Has Been Enabled for an AS Group?
- How Do I Enable Automatic Initialization of EVS Disks on Instances that Have Been Added to an AS Group During Scaling Actions?
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General
- Videos
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Dynamic Scaling
Before using AS to perform scaling actions, you must specify how to perform the scaling actions to dynamically expand resources.
If the demands change frequently, you can configure alarm-based policies to scale resources. When the conditions for invoking an AS policy are met, AS automatically changes the expected number of instances to trigger a scaling action to scale up or down resources. For details about how to create an alarm policy, see Creating an AS Policy.
Consider a train ticket booking application. If the CPU usage of the instances that run the application goes up to 90%, an instance needs to be added to ensure that services run properly. If the CPU usage drops down to 30%, an instance needs to be deleted to prevent resource waste. To meet the requirements, you can configure two alarm policies. One policy is used to add one instance if the maximum CPU usage exceeds 90%. For details, see Figure 1. The other policy is used to remove an instance if the minimum CPU usage drops below 30%. For details, see Figure 2.
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