What Is Auto Scaling?

AS Introduction

Auto Scaling (AS) helps you automatically scale Elastic Cloud Server (ECS) and bandwidth resources to keep up with changes in demand based on pre-configured AS policies. It allows you to add ECS instances or increase bandwidths to handle load increases and also save money by removing resources that are sitting idle.


AS allows you to scale ECS instances and bandwidths.

  • Scaling control: You can configure AS policies, configure metric thresholds, and schedule when different scaling actions are taken. AS will trigger scaling actions on a repeating schedule, at a specific time, or when the configured thresholds are reached.

  • Policy configuration: You can configure alarm-based, scheduled, and periodic policies as needed.

  • Alarm-based policies: You can configure scaling actions to be taken when alarm metrics such as vCPU, memory, disk, and inbound traffic reach the thresholds.

  • Scheduled policies: You can schedule scaling actions to be taken at a specific time.

  • Periodic policies: You can configure scaling actions to be taken at scheduled intervals, at specific time, or within a particular time range.

  • When Cloud Eye generates an alarm for a monitoring metric, for example, CPU usage, AS automatically increases or decreases the number of instances in the AS group or the bandwidths.

  • When the configured triggering time arrives, a scaling action is triggered to increase or decrease the number of ECS instances or the bandwidths.

**Figure 1** AS architecture

Figure 1 AS architecture

Accessing AS

The public cloud provides a web-based service management platform. You can access AS using HTTPS-compliant application programming interfaces (APIs) or the management console.

  • Calling APIs

    Use this method if you are required to integrate AS on the public cloud into a third-party system for secondary development. For more information, see Auto Scaling API Reference.

  • Management console

    Use this method if you do not need to integrate AS with a third-party system.

    After registering on the public cloud, log in to the management console and select Auto Scaling from the service list on the homepage.