Compute - ECR (Elastic Container Registry)

Question 1

What is Elastic Container Registry (ECR)?

Answer 1

• ECR is a fully managed service by AWS.
• It provides a secure location to store and manage docker images.
• It allows developers to push, pull, and manage their docker images in a central and secure location.

Question 2

What components are used in ECR?

Answer 2

• Registry: Hosts and stores docker images and creates image repositories.
• Authorization token: Used to authenticate the docker client with the registry.
• Repository: Groups together and secures docker images.
• Repository policy: Controls access and permissions for specific users.
• Image: Docker image stored in the repository.

Question 3

How can you access your ECR registry?

Answer 3

• The default URL for the registry is: https://aws_account_id.dkr.ecr.region.amazonaws.com
• IAM policies and repository policies can control access to the registry and images.
• Docker clients need to be authenticated with an authorization token to access the registry.

Question 4

How can you authenticate a docker client with the ECR registry?

Answer 4

• Run the “aws ecr get-login” command with the AWS CLI to obtain an authorization token.
• Copy and paste the output docker login command into the docker terminal.
• This associates the docker CLI with the default registry and provides authorization for 12 hours.

Question 5

What are repositories in ECR?

Answer 5

• Repositories are objects within the registry that group and secure docker images.
• Multiple repositories can be created within a registry to organize and manage images.
• IAM policies and repository policies control access and permissions for each repository.

Question 6

How can access to ECR be controlled?

Answer 6

• IAM managed policies: AmazonEC2ContainerRegistryFullAccess, AmazonEC2ContainerRegistryPowerUser, and AmazonEC2ContainerRegistryReadOnly.
• Repository policies: Resource-based policies that determine access and permissions for users.
• Access to the “ecr get authorization token” API call is required for AWS users to gain access.

Question 7

How can you push and pull docker images from ECR?

Answer 7

• Use the “docker push” command to push an image into ECR.
• Use the “docker pull” command to retrieve an image from ECR.
• Refer to the provided documentation links for more information on performing these actions.