ASG and lifecycle hooks

Transcript

1. ASG and lifecycle hooks
   ASG and lifecycle hooks
   Sibi Prabakaran
   May 15, 2019
   

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2. Objective
   Objective
   Run scripts before terminating EC2 instances of an ASG group
   Like de registering the instances from ALB.
   Inform Kubernetes/Nomad that this instance is in-eligible for new
   tasks
   

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3. Terminology
   Terminology
   ASG: Collection of EC2 instances with policies on
   scaling.
   Lifecycle hooks:
   Like callbacks which can be added to ASG.
   

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4. ASG Events
   ASG Events
   Scale Out: Instructs ASG to launch new instances.
   Scale In: Instructs ASG to detach EC2 instances.
   Fired on
   Manually increasing the size of the group
   Based on Policy (like demand)
   Based on Schedule
   

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5. ASG Events (2)
   ASG Events (2)
   On receiving the events, the ASG will put the instance into Pending or
   Terminating state. If you have defined any lifecycle hooks - that will happen
   in this state.
   Timeouts
   

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6. lifecycled
   lifecycled
   Daemon built by buildkite for gracefully handling EC2 scaling events.
   When a termination notice is received, lifecycled runs a user provided script
   before proceeding to shutdown the instance.
   Repo: https://github.com/buildkite/lifecycled
   

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7. Demo
   Demo
   PR: https://github.com/fpco/terraform-aws-foundation/pull/189
   Testing instance: http://18.222.32.132:3000
   Based on vpc scenario 1 (VPC with single public subnet).
   ASG with two EC2 instances, also registered with ELB.
   Instances has lifecycled installed on it.
   

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8. Questions
   Questions
   

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