High-level steps for implementing a blue/green deployment with AWS Fargate
- Create a new task definition for the updated version of your application, using the AWS Management Console or the AWS CLI.
- Use the new task definition to launch a new Fargate service in a new environment (e.g. a new VPC or a different availability zone).
- Test the new environment to ensure that the updated application is working as expected.
- Set up a load balancer to route traffic to the new environment and perform a canary deployment, where a small percentage of traffic is sent to the new environment to test it further.
- Monitor the performance of the new environment and the existing environment to ensure that there are no issues.
- Once you are confident that the new environment is working properly, you can switch the load balancer to route all traffic to the new environment, effectively performing the blue/green deployment.
- You can then decommission the old environment once the new environment is handling all traffic.
Here is an example of how you might implement a blue/green deployment with AWS Fargate using the AWS CLI:
- Create a new task definition for the updated version of your application using the
register-task-definition
command:
aws ecs register-task-definition --family my-app-family --container-definitions file://my-app-containers.json
- Use the new task definition to launch a new Fargate service in a new environment, such as a new VPC:
aws ecs create-service --cluster my-app-cluster --service-name my-app-service --task-definition my-app-family --launch-type "FARGATE" --network-configuration "awsvpcConfiguration={subnets=[subnet-12345678,subnet-87654321],securityGroups=[sg-12345678]}"
- Test the new environment to ensure that the updated application is working as expected. You can do this by accessing the application using the DNS name or IP address of the new environment.
- Set up a load balancer to route traffic to the new environment and perform a canary deployment using the
create-service
command:
aws ecs create-service --cluster my-app-cluster --service-name my-app-canary-service --task-definition my-app-family --launch-type "FARGATE" --network-configuration "awsvpcConfiguration={subnets=[subnet-12345678,subnet-87654321],securityGroups=[sg-12345678]}" --load-balancer-info "targetGroupArn=arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/my-app-target-group/1234567890abcd,containerName=my-app-container,containerPort=80"
- Monitor the performance of the new environment and the existing environment to ensure that there are no issues.
- Once you are confident that the new environment is working properly, you can switch the load balancer to route all traffic to the new environment using the
update-service
command:
aws ecs update-service --cluster my-app-cluster --service my-app-service --desired-count 0