AWS Autoscaling Policies
- Target Tracking Policy: This tries to maintain the percentage defined. To maintain the metric defined aws will perform scale out and in.
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In the below scaling policies we define when to scale out and when to scale in. Refer Here for official docs
- Step Scaling:
- Simple Scaling:
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Create an autoscaling group withouth selecting scaling policy
- Simple Scaling has an extra cooldown period during which scaling will not happen
Questions to be addressed
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How do i upgrade the images without downtime when there is a new version of the image/application/os upgrade
- Create a new version of the launch template
- Navigate to asg and perform instance refresh
- For screenshots watch classroom video
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Exercise:
- Create a launch template with ubuntu and in userdata install apache
- Create a autoscaling with load balancer
- Now after everything is running
- Create a new version of the launch template where in userdata install nginx
- Perform instance refresh of asg and wait for the nginx to be updated.
