How to fix Error: Error creating ECR Repository: RepositoryAlreadyExistsException in Terraform

First, confirm the ECR repository actually exists in your AWS account:

aws ecr describe-repositories --repository-names your-repo-name

If it returns repository details, it exists. Note the exact repository name for the next step.

Use terraform import to register the existing repository with your Terraform state:

terraform import aws_ecr_repository.my_repo your-repo-name

Replace aws_ecr_repository.my_repo with your resource identifier in Terraform and your-repo-name with the actual ECR repository name in AWS.

If you're using count or for_each in your resource definition, adjust the import command:

For count:

terraform import 'aws_ecr_repository.repo[0]' your-repo-name

For for_each:

terraform import 'aws_ecr_repository.repo["mykey"]' your-repo-name

After importing, run terraform plan to ensure Terraform now recognizes the repository and won't try to recreate it:

terraform plan

You should see no changes to the ECR repository resource. If there are still changes, review the resource configuration to ensure it matches the actual AWS resource.

To prevent this error in the future, ensure each environment has uniquely named repositories. Use Terraform variables and naming conventions:

resource "aws_ecr_repository" "app" {
  name = "${var.environment}-${var.app_name}"
}

For example: dev-myapp, staging-myapp, prod-myapp.

Configure lifecycle rules and policies to manage repositories consistently:

resource "aws_ecr_repository" "app" {
  name                 = "my-app"
  image_tag_mutability = "MUTABLE"

  image_scanning_configuration {
    scan_on_push = true
  }

  lifecycle {
    prevent_destroy = true
  }
}

The prevent_destroy flag helps prevent accidental deletions.