Amazon EC2 Auto-Scaling Concepts: Difference between revisions
| Line 15: | Line 15: | ||
With auto-scaling, an application gets better ''fault tolerance'': auto-scaling can detect instance failure, terminate it and launch a new instance to replace it. Auto-scaling uses [[Amazon AWS Concepts#Availability_Zone|availability zones]]: if one availability zone becomes unavailable, auto-scaling will launch instances in another one, to compensate. | With auto-scaling, an application gets better ''fault tolerance'': auto-scaling can detect instance failure, terminate it and launch a new instance to replace it. Auto-scaling uses [[Amazon AWS Concepts#Availability_Zone|availability zones]]: if one availability zone becomes unavailable, auto-scaling will launch instances in another one, to compensate. | ||
The application also gets better ''availability'': | The application also gets better ''availability'': the right amount of capacity is brought on-line (or shut-down) via auto-scaling. | ||
=Auto-Scaling Group= | =Auto-Scaling Group= | ||
Revision as of 23:30, 11 October 2016
External
- Auto-scaling User Guide http://docs.aws.amazon.com/autoscaling/latest/userguide/
Internal
Overview
Auto-scaling is an Amazon EC2 functionality that insures that an optimal number of EC2 instances are started and maintained running, to handle the load of a specific application. The EC2 instances whose number is controlled this way are part of an auto-scaling group.
Auto-scaling allows for scaling plans, which control the number of active instances as the demand on the application increases or decreases.
With auto-scaling, an application gets better fault tolerance: auto-scaling can detect instance failure, terminate it and launch a new instance to replace it. Auto-scaling uses availability zones: if one availability zone becomes unavailable, auto-scaling will launch instances in another one, to compensate.
The application also gets better availability: the right amount of capacity is brought on-line (or shut-down) via auto-scaling.
Auto-Scaling Group
Auto-scaling ensures that the number of EC2 instances in an auto-scaling group does not go below a minimum size and above a maximum size. The group has a desired capacity.