Auto Scaling

Features

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  Features

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    Auto Scaling

    Automatically increase or decrease ECS instances according to customers’ business needs.

    
    

    Support Server Load Balancer Configuration

    When adding or releasing ECS instances, the service automatically attaches or detaches the instances to the Server Load Balancer.

    
    

    Support RDS Whitelist

    When adding ECS instances, the service automatically adds instance IPs to the whitelist of RDS instances. Likewise, when releasing ECS instances the service automatically delists instance IPs from the whitelist.

    
    
    
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  Scale Mode

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    Scheduled Mode

    Configure scheduled tasks, and add or remove ECS instances with a fixed time window. Can be combined with dynamic mode.

    
    

    Dynamic Mode

    Dynamically add or remove ECS instance(s) based on CloudMonitor metrics (ie. CPU and memory ratio).

    
    

    Fixed Mode

    The “minimal size” setting allows you to employ the minimal number of ECS instances required to support business-as-usual levels of activity.

    
    

    Auto-config Server Load Balancer and RDS

    When adding or removing ECS instances, the service automatically attaches or detaches instances to the Server Load Balancer, and adds these servers to the whitelist of RDS instances.

    
    
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  Note

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    Auto Scaling is subject to the following constraints:

    
    

    - Applications that deploy Auto Scaling ECS instances must be stateless and horizontally scalable. ECS instances created by Auto Scaling cannot be used to save application status (ie. session status) or related data (ie. databases and logs). This is because Auto Scaling automatically releases ECS instances. Status information can be saved to an independent state server database (i.e. ApsaraDB for RDS), shared cache (i.e. ApsaraDB for Memcache), or centralized log storage (i.e. Log Service).
    
    - Each user can only create a limited number of scaling groups, scaling configurations, scaling rules, scaling ECS instances, and scheduled tasks..