- 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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Configuring an Instance Removal Policy
When instances are automatically removed from your AS group, the instances that are not in the currently used AZs will be removed first. Besides, AS will check whether instances are evenly distributed in the currently used AZs. If the load among AZs is unbalanced, AS balances load among AZs when removing instances. If the load among AZs is balanced, AS removes instances following the pre-configured instance removal policy.
AS supports the following instance removal policies:
- Oldest instance: The oldest instance is removed from the AS group first. Use this policy if you want to upgrade instances in an AS group to a new ECS type. You can gradually replace instances of the old type with instances of the new type.
- Newest instance: The newest instance is removed from the AS group first. Use this policy if you want to test a new AS configuration but do not want to keep it in production.
- Oldest instance created from oldest AS configuration: The oldest instance created from the oldest configuration is removed from the AS group first. Use this policy if you want to update an AS group and phase out the instances created from a previous AS configuration.
- Newest instance created from oldest AS configuration: The newest instance created from the oldest configuration is removed from the AS group first.
Manually added instances are the last to be removed, and if AS does remove a manually added instance, it only removes the instance. It does not delete the instance. If multiple manually added instances must be removed, AS preferentially removes the earliest-added instance first.
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