super hard
What is an on-demand instance?
An on-demand instance is a pay-as-you-go EC2 instance with no upfront cost or long-term commitment.
What is a container?
A container is a lightweight, portable unit that packages an application and its dependencies so it can run consistently across environments.
What is AWS Lambda?
AWS Lambda is a serverless compute service that lets you run code without provisioning or managing servers.
What is a spot instance?
A spot instance uses unused EC2 capacity at a discounted price but can be interrupted when demand increases.
How are containers different from virtual machines?
Containers differ from virtual machines because they do not include a full operating system and instead share the host OS, making them smaller and faster to start.
What is a Lambda function?
A Lambda function is the actual piece of code you upload to AWS Lambda that runs in response to events.
When should you use reserved instances?
Reserved instances should be used when you have predictable, steady workloads over a long period and want lower costs.
What is Docker used for?
Docker is used to build, package, and run applications in containers.
What is the benefit of Elastic Beanstalk?
Elastic Beanstalk simplifies application deployment by automatically handling infrastructure tasks like provisioning, scaling, and load balancing so developers can focus on writing code.
What are the four pillars of cost optimization?
The four pillars of cost optimization are right-sizing resources, increasing elasticity, choosing the optimal pricing model, and optimizing storage choices.
What is the difference between ECS and EKS?
ECS is a fully managed container orchestration service built by AWS, while EKS is a managed service that runs Kubernetes, an open-source container orchestration platform.
What is an execution role in AWS Lambda, and why is it important?
An execution role in AWS Lambda is an IAM role that defines what AWS services the Lambda function is allowed to access, ensuring secure and controlled permissions.
Design a cost-optimized strategy for a workload that has steady baseline usage but occasional spikes.
A cost-optimized strategy would use reserved instances for the steady baseline workload, on-demand or spot instances for handling occasional spikes, automatic scaling to adjust capacity dynamically, and storage optimization to reduce unnecessary costs.
Explain how Kubernetes manages containers using nodes and pods.
Kubernetes manages containers by organizing them into pods, which are groups of containers, and running those pods on nodes, which are clusters of compute resources, allowing it to schedule, scale, and maintain containerized applications efficiently.
A Lambda function needs to access data in another AWS service (like S3). Describe the steps required to securely grant this access without using hardcoded credentials.
To allow a Lambda function to access another AWS service like S3 securely, you create an IAM role with the required permissions, attach it as the function’s execution role, define policies that grant only necessary access, and avoid hardcoding credentials by letting AWS automatically provide temporary credentials to the function.