AWS Copilot CLI is an open source command line interface for running containers on AWS App Runner, Amazon Elastic Container Service (ECS), and AWS Fargate.

You can use Copilot to run containers on Fargate’s serverless compute with Graviton2 processors and benefit from improved price performance.

Graviton is not the default for Copilot, but read on to find out how to change the architecture to Arm.

Before you begin

You will need Docker and Copilot on your local computer to follow the instructions below.

Your local computer can be Linux or macOS.

There are plenty of places to find Docker installation instructions. One option is the Docker install guide.

You will also need an AWS account.

To create an account, go to https://aws.amazon.com and click on Create an AWS Account in the top right corner. Follow the instructions to register. See the Creating an AWS account documentation for full instructions.

Make sure to configure your access key ID and secret access key, which are used to sign programmatic requests that you make to AWS. Refer to AWS Credentials for a quick summary of how to run aws configure. The install guide also covers how to install the AWS CLI. Make a note of the AWS region you set with aws configure so you can see the resources created by Copilot in the AWS console.

If you are using Docker on Linux you will need to install QEMU to build container images for both the arm64 and the amd64 architectures.

sudo apt-get install qemu-user-static

Docker Desktop for macOS includes the ability to build for multiple architectures, so you don't need to do anything extra.

To install Copilot on Arm Linux:

sudo curl -Lo /usr/local/bin/copilot https://github.com/aws/copilot-cli/releases/latest/download/copilot-linux-arm64 \
   && sudo chmod +x /usr/local/bin/copilot \
   && copilot --help

To install Copilot on macOS:

curl -Lo copilot https://github.com/aws/copilot-cli/releases/latest/download/copilot-darwin && chmod +x copilot && sudo mv copilot /usr/local/bin/copilot && copilot --help

Create an example application

To try Copilot on Graviton2 processors, you can use the same Go application used in Multi-architecture Kubernetes clusters on Amazon EKS.

Use an editor to create the 3 files below.

Create a file named hello.go with the contents:

// Copyright 2022 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
    "fmt"
    "log"
    "net/http"
    "runtime"
)

func handler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintf(w, "Hello from CPU PLATFORM:%s/%s",
        runtime.GOOS, runtime.GOARCH)
}

func main() {
    http.HandleFunc("/", handler)
    log.Fatal(http.ListenAndServe(":8080", nil))
}

Next, create a file named go.mod with the following two lines:

module example.com/arm
go 1.21

Create a third file named Dockerfile with the contents:

#
# Build: 1st stage
#
FROM golang:1.21-alpine as builder
ARG TARCH
WORKDIR /app
COPY go.mod .
COPY hello.go .
RUN go build -o /hello && \
    apk add --update --no-cache file && \
    file /hello

#
# Release: 2nd stage
#
FROM alpine
WORKDIR /
COPY --from=builder /hello /hello
RUN apk add --update --no-cache file
CMD [ "/hello" ]

The application listens on port 8080 and prints the architecture of the machine.

Deploy the application with Copilot

You can deploy the application with a single command:

copilot init --app go-arch               \
  --name api                             \
  --type 'Load Balanced Web Service'     \
  --dockerfile './Dockerfile'            \
  --env test                             \
  --port 8080                            \
  --deploy

The default architecture is amd64. The copilot command builds the container on your local machine for amd64, pushes it to the container registry, and creates everything needed to run on AWS Fargate.

You can also specify an existing container image using --image instead of --dockerfile. Make sure the image is a multi-architecture image supporting both arm64 and amd64.

While you are waiting for the command to complete you can look in your AWS account and see the resources created in AWS S3, CloudFormation, and ECS.

When the copilot command completes, the URL of the load balancer is printed.

Visit the URL in your browser and see the printed message.

To access the application from the command line, run curl with the URL.

For example:

curl -w '\n' http://go-arc-Publi-UvaFr7DQF5ud-988490958.us-west-2.elb.amazonaws.com

The output is:

Hello from CPU PLATFORM:linux/amd64

You can also check running status using:

copilot svc status

The output is similar to:

Found only one deployed service api in environment test
Task Summary

  Running   ██████████  1/1 desired tasks are running
  Health    ██████████  1/1 passes HTTP health checks
            ██████████  1/1 passes container health checks

Tasks

  ID        Status      Revision    Started At     Cont. Health  HTTP Health
  --        ------      --------    ----------     ------------  -----------
  7779652d  RUNNING     1           7 minutes ago  HEALTHY       HEALTHY

Migrate to Graviton

To move from amd64 to arm64 edit the file copilot/api/manifest.yml and change the platform entry from linux/x86_64 to linux/arm64.

If you don't have a platform entry, add one after the existing entries. Either way, you should have this line in your manifest.yml file:

platform: linux/arm64

You are now ready to run on Graviton2.

Save the file and redeploy the application using:

copilot svc deploy 

Copilot rebuilds the container image for the arm64 architecture, pushes the image to the container registry and deploys the new image.

If you look in your AWS console and visit the task configuration in ECS, you will see the task now shows ARM64 as the architecture.

Visit the URL again using a browser or the same curl command and the message prints arm64.

Hello from CPU PLATFORM:linux/arm64

Open a shell in the container

If you need to troubleshoot a container, you can use Copilot to connect.

copilot svc exec

Answer yes to install the Session Manager plugin, and you have a shell into the running container.

Starting session with SessionId: ecs-execute-command-0f1f212e5ff00ec05
/ # 

You can make changes to the container and do any needed investigation. Copilot is an easy way to connect to running containers.

Summary

You have deployed a containerized application on Fargate running AWS Graviton2 processors using Copilot. The Copilot CLI makes it much easier to create the required resources and easily make changes using the manifest.yml file.

There doesn't seem to be a way to specify arm64 on the initial copilot init command, but it would be a useful enhancement.

Clean up the AWS resources

Delete the resources created by Copilot by running:

copilot app delete