Design for New Solutions

1. A DevOps team uses AWS OpsWorks Stacks to manage a multi-tier application. They need custom configuration to run automatically whenever a new instance joins or leaves a layer. Which OpsWorks Lifecycle Event should their Chef recipe be assigned to?

• A.Setup — runs once when an instance finishes booting, used for initial software installation and configuration.
• B.Configure — runs on ALL instances in the stack whenever an instance enters or leaves the online state.✓ Correct
• C.Deploy — runs only on instances in the target layer when an app deployment command is issued.
• D.Undeploy — runs when an application version is removed from a specific set of instances in a layer.

2. An OpsWorks Stacks layer runs a Node.js application. An engineer wants to ensure that when an instance in the layer is stopped gracefully, all active connections are drained before the process exits. To which Lifecycle Event should this custom Chef recipe be attached?

• A.Deploy — triggered each time a new application version is pushed to the instances in the layer.
• B.Configure — triggered across all stack instances when topology changes occur such as scaling events.
• C.Undeploy — triggered to remove a specific application version from a designated set of instances.
• D.Shutdown — triggered on an instance when a stop command is issued, before the instance is terminated.✓ Correct

3. A retail company needs to deploy a critical application update to Elastic Beanstalk with zero downtime and the ability to instantly roll back to the previous version if issues arise. The team can afford to run double the infrastructure temporarily. Which deployment policy best meets these requirements?

• A.All at once — deploys to all instances simultaneously, causing brief downtime but completing the fastest.
• B.Rolling — updates instances in small batches, maintaining partial capacity throughout the deployment.
• C.Rolling with additional batch — launches extra instances first so full capacity is maintained during rolling updates.
• D.Immutable — launches a completely new set of instances with the new version, enabling instant rollback by terminating them.✓ Correct

4. A development team is deploying an image-processing pipeline. A web front-end receives upload requests, while a back-end component processes jobs asynchronously from a queue. How should these components be deployed in Elastic Beanstalk?

• A.Deploy both components as separate Web Server tier environments, each with its own load balancer and Auto Scaling group.
• B.Deploy the front-end as a Web Server tier and the back-end as a Worker tier that reads from an SQS queue automatically.✓ Correct
• C.Deploy both components as a single Web Server tier environment and use threads to handle background processing inline.
• D.Deploy the front-end as a Worker tier and the back-end as a Web Server tier, since Worker tiers handle HTTP traffic more efficiently.

5. A security team requires that every container task in their ECS Fargate cluster have its own isolated network interface so that security groups can be applied at the individual task level. Which network mode satisfies this requirement, and what does Fargate assign to each task?

• A.Bridge mode — containers share the host's network namespace and are accessed via port mappings on the EC2 instance.
• B.Host mode — containers bind directly to the EC2 host network interface, sharing the host's IP address and port space.
• C.awsvpc mode — each task receives its own Elastic Network Interface (ENI) and private IP address from the VPC subnet.✓ Correct
• D.Overlay mode — tasks communicate through a virtual network overlay managed by Docker Swarm across multiple hosts.