# Re-architecting as microservices in Linux containers
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A microservices architecture is an approach to developing a single application as a suite of small services. Each service runs in its own process and communicates with other services through lightweight mechanisms. This approach breaks down a monolithic application into smaller services, where each service serves a single purpose and is deployed as a container.

## Use cases
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This migration strategy is useful if:
+ You want to break your monolithic system into microservices.
+ You have the resources and time available for refactoring.
+ You can resolve all .NET Framework dependencies.
+ You have a long-running application.

## Advantages
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This migration approach provides the following benefits, when compared with on-premises .NET applications:
+ Faster innovation because it’s easier to add new features in a microservices architecture
+ High availability and reliability
+ Increased agility and on-demand scalability
+ Independent deployment and modern continuous integration and continuous deployment (CI/CD) pipelines
+ Strong module boundaries and technical diversity

## Disadvantages
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+ Effort and cost of refactoring
+ Potential operational complexity

## AWS services
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You can use the following AWS services to develop a microservices-based system:
+ [Amazon API Gateway](https://aws.amazon.com/api-gateway)
+ [Amazon Simple Notification Service](https://aws.amazon.com/sns) (Amazon SNS)
+ [Amazon Simple Queue Service](https://aws.amazon.com/sqs) (Amazon SQS)
+ [Amazon ECS](https://aws.amazon.com/ecs)
+ [Amazon EKS](https://aws.amazon.com/eks)
+ [AWS Lambda](https://aws.amazon.com/lambda)
+ [AWS Fargate](https://aws.amazon.com/fargate)
+ [CloudFormation](https://aws.amazon.com/cloudformation) or [AWS Cloud Development Kit (AWS CDK)](https://aws.amazon.com/cdk)
+ [AWS Identity and Access Management](https://aws.amazon.com/iam) (IAM)
+ [Amazon Simple Storage Service](https://aws.amazon.com/s3) (Amazon S3)
+ [Amazon ECR](https://aws.amazon.com/ecr)

## Tools
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AWS Professional Services offers custom tools and services to help you refactor your monolithic applications into microservices.

## Deployment decisions
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You can choose from five deployment options:
+ If you want complete control over the configuration of your compute environment, including memory and storage settings, and control over operating system patches: deploy your application as a Linux container on an EC2 instance.
+ If you want the container to be managed by Kubernetes and run as a serverless container: deploy your application as a Linux container on Amazon EKS with Fargate.
+ If you want the container to be managed by Amazon ECS and run as a serverless container: deploy your application as a Linux container on Amazon ECS with Fargate.
+ If you want the container to be managed by Kubernetes, but you want to manage the compute resources of the container yourself: deploy your application as a Linux container on Amazon EKS.
+ If you want the container to be managed by Amazon ECS, but you want to manage the compute resources of the container yourself: deploy your application as a Linux container on Amazon ECS.

 ![\[Refactoring .NET applications as microservices in Linux containers on AWS\]](http://docs.aws.amazon.com/prescriptive-guidance/latest/modernization-net-applications/images/rearchitect-linux.png)