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EC2 Demo 13 - Autoscaling with Target Tracking Policy

Step-01: Introduction

V1-Terraform-Manifests: LC & ASG & TTSP & ALB & Notifications

Module-1: ASG & LC & ALB

  • Create Launch Configuration
  • Create Autoscaling Group
  • Map it with ALB (Application Load Balancer)

Module-2: - TTSP (Target Tracking Scaling Policies)

  • Create Resource: aws_autoscaling_policy
  • ASGAverageCPUUtilization
  • ALBRequestCountPerTarget
  • Terraform Import for ALBRequestCountPerTarget Resource Label finding

Module-3: Autoscaling Notifications

  • Create SNS Topic aws_sns_topic
  • Create SNS Topic Subscription aws_sns_topic_subscription
  • Create Autoscaling Notification Resource aws_autoscaling_notification

Module-4: Scheduled Actions

  • Create a scheduled action to increase capacity at 7am
  • Create a scheduled action to decrease capacity at 5pm
# Import State
$ terraform import aws_autoscaling_schedule.resource-name auto-scaling-group-name/scheduled-action-name
terraform import aws_autoscaling_schedule.capacity_increase_during_business_hours    myapp1-asg-20210329100544375800000007/capacity_increase_during_business_hours  
-> using terraform import get values for recurrence argument (cron format)

# UTC Timezone converter
https://www.worldtimebuddy.com/utc-to-est-converter

Module-5: Changes to ASG

  • Change Desired capacity to 3 desired_capacity = 3 and test
  • Any change to ASG, do a instance refresh
  • Instance Refresh is not available in this ASG module, we will learn this during Launch Template + ASG with Resources
  instance_refresh {
    strategy = "Rolling"
    preferences {
      min_healthy_percentage = 50
    }
    triggers = ["tag"]
  }

Module-6: Change to Launch Configuration

  • What happens?
  • In next scale-in event changes will be adjusted [or] if instance refresh present and configured in this module it updates ASG with new LC ID, instance refresh should kick in.
  • We will test this with next scale-in event - Run postman runner test
  • Lets see that practically

Step-02: ASG with ELB with Simple Scaling

V2-Terraform-Manifests: Simple Scaling

  • Implement Simple Scaling

V3-Terraform-Manifests: Step Scaling &

V5-Terraform-Manifests: Lifecycle Hooks

V6-Terraform-Manifests: Modify LC and ASG

V7-Terraform-Manifests: Monitoring

Instance Refresh

Step-02: Get Resource LABEL for TTS Policy ALBRequestCount policy

$ terraform import aws_autoscaling_policy.test-policy asg-name/policy-name

terraform import aws_autoscaling_policy.dkalyan-test-policy myapp1-asg-20210329045302504300000007/TP1

References