Master AWS ECR: Key Interview Questions and Answers Explained

I can provide you with the top 10 AWS ECR (Elastic Container Registry) interview questions and answers. Let's begin:

Q1: What is AWS ECR?
A1: AWS ECR is a fully managed Docker container registry service provided by Amazon Web Services (AWS). It allows users to store, manage, and deploy container images using Docker and supports private container image repositories.

Q2: How does ECR differ from Docker Hub?
A2: ECR is a private registry that offers improved security and access control compared to Docker Hub, which is a public registry. ECR provides seamless integration with other AWS services and allows you to store container images within your AWS infrastructure.

Q3: How can you authenticate and access your ECR repository?
A3: ECR provides two methods of authentication: AWS CLI (Command Line Interface) and IAM (Identity and Access Management). IAM roles can be created to grant specific permissions for accessing ECR repositories.

Q4: What is the difference between ECR and ECS (Elastic Container Service)?
A4: ECR is a container registry for storing and managing container images, while ECS is a container orchestration service that allows you to run and manage containers. ECR is often used in conjunction with ECS for deploying containers.

Q5: How can you push a local Docker image to ECR?
A5: To push a local Docker image to ECR, you can use the following steps:

1. Build your Docker image locally.

2. Tag the image with the ECR repository URI.

3. Authenticate with ECR using the AWS CLI.

4. Push the image to ECR using the Docker CLI.

Q6: What is the ECR lifecycle policy?
A6: ECR lifecycle policies automate the process of cleaning up unused or untagged container images in your repository. You can define rules based on image age or tag status to automatically remove images, helping you optimize storage costs.

Q7: Can ECR be used outside of AWS?
A7: No, ECR is an AWS-specific service and can only be used within the AWS ecosystem. If you need a container registry outside of AWS, you can consider using other options like Docker Hub or Google Container Registry.

Q8: How can you control access to ECR repositories?
A8: Access to ECR repositories can be controlled using IAM policies. You can create IAM policies that grant or restrict users, groups, or roles from performing specific actions, such as pulling or pushing container images.

Q9: Can you share container images between AWS accounts?
A9: Yes, you can share container images between AWS accounts by using resource policies. By creating a resource policy, you can grant permissions to other AWS accounts, allowing them to access and pull images from your ECR repositories.

Q10: How does ECR handle scalability and availability?
A10: ECR is designed to be highly scalable and available. It automatically scales storage capacity as needed and can handle high request rates. Additionally, ECR automatically replicates images across multiple AWS availability zones within a region for durability and fault tolerance.

These are the top 10 AWS ECR interview questions and answers. Familiarity with these topics should help you in your cloud engineering role and demonstrate your understanding of ECR. Good luck!