Running Flatcar Container Linux with AWS EC2 Container Service

    Amazon EC2 Container Service (ECS) is a container management service which provides a set of APIs for scheduling container workloads across EC2 clusters. It supports Flatcar Container Linux with Docker containers.

    Your Flatcar Container Linux machines communicate with ECS via an agent. The agent interacts with Docker to start new containers and gather information about running containers.

    Set up a new cluster

    When booting your Flatcar Container Linux Machines on EC2 , configure the ECS agent to be started via Ignition .

    Be sure to change ECS_CLUSTER to the cluster name you’ve configured via the ECS CLI or leave it empty for the default. Here’s a full config example:

    storage:
      files:
        - path: /var/lib/iptables/rules-save
          filesystem: root
          mode: 0644
          contents:
            inline: |
              *nat
              -A PREROUTING -d 169.254.170.2/32 -p tcp -m tcp --dport 80 -j DNAT --to-destination 127.0.0.1:51679
              -A OUTPUT -d 169.254.170.2/32 -p tcp -m tcp --dport 80 -j REDIRECT --to-ports 51679
              COMMIT          
        - path: /etc/sysctl.d/localnet.conf
          filesystem: root
          mode: 0644
          contents:
            inline: |
                        net.ipv4.conf.all.route_localnet=1
    
    systemd:
     units:
       - name: iptables-restore.service
         enable: true
       - name: systemd-sysctl.service
         enable: true
       - name: amazon-ecs-agent.service
         enable: true
         contents: |
           [Unit]
           Description=AWS ECS Agent
           Documentation=https://docs.aws.amazon.com/AmazonECS/latest/developerguide/
           Requires=docker.socket
           After=docker.socket
    
           [Service]
           Environment=ECS_CLUSTER=your_cluster_name
           Environment=ECS_LOGLEVEL=info
           Environment=ECS_VERSION=latest
           Restart=on-failure
           RestartSec=30
           RestartPreventExitStatus=5
           SyslogIdentifier=ecs-agent
           ExecStartPre=-/bin/mkdir -p /var/log/ecs /var/ecs-data /etc/ecs
           ExecStartPre=-/usr/bin/touch /etc/ecs/ecs.config
           ExecStartPre=-/usr/bin/docker kill ecs-agent
           ExecStartPre=-/usr/bin/docker rm ecs-agent
           ExecStartPre=/usr/bin/docker pull amazon/amazon-ecs-agent:${ECS_VERSION}
           ExecStart=/usr/bin/docker run \
               --name ecs-agent \
               --env-file=/etc/ecs/ecs.config \
               --volume=/var/run/docker.sock:/var/run/docker.sock \
               --volume=/var/log/ecs:/log \
               --volume=/var/ecs-data:/data \
               --volume=/sys/fs/cgroup:/sys/fs/cgroup:ro \
               --volume=/run/docker/execdriver/native:/var/lib/docker/execdriver/native:ro \
               --publish=127.0.0.1:51678:51678 \
               --publish=127.0.0.1:51679:51679 \
               --env=ECS_AVAILABLE_LOGGING_DRIVERS='["awslogs","json-file","journald","logentries","splunk","syslog"]'
               --env=ECS_ENABLE_TASK_IAM_ROLE=true \
               --env=ECS_ENABLE_TASK_IAM_ROLE_NETWORK_HOST=true \
               --env=ECS_LOGFILE=/log/ecs-agent.log \
               --env=ECS_LOGLEVEL=${ECS_LOGLEVEL} \
               --env=ECS_DATADIR=/data \
               --env=ECS_CLUSTER=${ECS_CLUSTER} \
               amazon/amazon-ecs-agent:${ECS_VERSION}
    
           [Install]
           WantedBy=multi-user.target       
    

    The example above pulls the latest official Amazon ECS agent container from the Docker Hub when the machine starts. If you ever need to update the agent, it’s as simple as restarting the amazon-ecs-agent service or the Flatcar Container Linux machine.

    If you want to configure SSH keys in order to log in, mount disks or configure other options, see the Container Linux Configs documentation .

    For more information on using ECS, check out the official Amazon documentation .