How do I mount an Amazon EFS file system on an Amazon ECS container or a task that runs on Fargate?

Resolution

To mount an Amazon EFS file system on a Fargate task or container, you must first create a task definition. Next, make that task definition available to the containers in your task across all Availability Zones in your AWS Region. Finally, your Fargate tasks use Amazon EFS to automatically mount the file system to the tasks that you specify in your task definition.

Important: The following resolution applies to the Fargate version 1.4.0 and later. These versions have persistent storage that you can define at the task and container level in Amazon ECS. Fargate versions 1.3.0 or earlier don't support the use of persistent storage with Amazon EFS.

Prerequisites

You must have the following:

• Amazon ECS cluster
• Amazon Virtual Private Cloud (Amazon VPC)
• Amazon EFS file system

Create and configure an Amazon EFS file system

1. Create an Amazon EFS file system, and then note the EFS ID and security group ID.
   Note: Your Amazon EFS file system, Amazon ECS cluster, and Fargate tasks must all be in the same VPC.
2. Edit the security group rules of your EFS file system to allow inbound connections. You must allow connections on port 2049 (Network File System, or NFS) from the security group associated with your Fargate task or service.
3. Update the security group of your Amazon ECS service to allow outbound connections on port 2049 to your Amazon EFS file system's security group.

Create a task definition

1. Open the Amazon ECS classic console.
2. From the navigation pane, choose Task Definitions, and then choose Create new Task Definition.
3. In the Select launch type compatibility section, choose FARGATE, and then choose Next Step.
4. In the Configure task and container definitions section, for Task Definition Name, enter a name for your task definition.
5. In the Volumes section, choose Add volume.
6. For Name, enter a name for your volume.
7. For Volume type, enter EFS.
8. For File system ID, enter the ID for your Amazon EFS file system.
   Note: You can specify custom options for Root directory, Encryption in transit, and EFS AWS Identity and Access Management (IAM) authorization. Or, you can accept the default option, where "/" is the root directory.
9. Choose Add.
10. In the Containers Definition section, choose Add container.
11. In the STORAGE AND LOGGING section, in the Mount points subsection, select the volume that you created for Source volume in step 5.
12. For Container path, choose your container path.
13. (Optional) In the ENVIRONMENT section, for Entry point, enter your entry point.
14. For Command, enter the [df ,-h] command to display the mounted file system.
    Note: You can use the entry point and command to test whether your Amazon EFS file system is successfully mounted. By default, the container exits after the df -h command successfully runs. The JSON task definition example in step 16 uses an infinite while loop to keep the task running.
15. Choose Add.
16. Enter your information for the remaining fields in the task definition wizard, and then choose Create.

In the following example, the JSON task definition uses an infinite loop to keep the task running. The task definition creates a data volume named efs-test. The nginx container mounts the host data volume at the Any_Container_Path path.

{
  "family": "sample-fargate-test",
  "networkMode": "awsvpc",
  "executionRoleArn": "arn:aws:iam::1234567890:role/ecsTaskExecutionRole",
  "containerDefinitions": [
    {
      "name": "fargate-app",
      "image": "nginx",
      "portMappings": [
        {
          "containerPort": 80,
          "hostPort": 80,
          "protocol": "tcp"
        }
      ],
      "essential": true,
      "entryPoint": [
        "sh",
        "-c"
      ],
      "command": [
        "df -h && while true; do echo \"RUNNING\"; done"
      ],
      "mountPoints": [
        {
          "sourceVolume": "efs-test",
          "containerPath": "Any_Container_Path"
        }
      ],
      "logConfiguration": {
        "logDriver": "awslogs",
        "options": {
          "awslogs-group": "AWS_LOG_GROUP_PATH",
          "awslogs-region": "AWS_REGION",
          "awslogs-stream-prefix": "AWS_STREAM_PREFIX"
        }
      }
    }
  ],
  "volumes": [
    {
      "name": "efs-test",
      "efsVolumeConfiguration": {
        "fileSystemId": "fs-123xx4x5"
      }
    }
  ],
  "requiresCompatibilities": [
    "FARGATE"
  ],
  "cpu": "256",
  "memory": "512"
}

Note: Replace fileSystemId, logConfiguration, containerPath, and other placeholder values with values for your custom configuration. Also, confirm that your task definition has an execution role Amazon Resource Name (ARN) to support the awslogs log driver.
To mount multiple EFS on different destinations (containerPath), you can define multiple mountPoints and volumes in your task definition.

Run a Fargate task and check your task logs

1. Run a Fargate task using the task definition that you created earlier.
   Important: You must use Fargate platform version 1.4.0 to run your task.
2. To verify that your Amazon EFS file system is successfully mounted to your Fargate container, check your task logs.
   The output of df-h looks similar to the following:

   2020-10-27 15:15:35Filesystem 1K-blocks Used Available Use% Mounted on
   
   2020-10-27 15:15:35
   overlay 30832548 9859324 19383976 34% /
   
   2020-10-27 15:15:35
   tmpfs 65536 0 65536 0% /dev
   
   2020-10-27 15:15:35
   shm 2018788 0 2018788 0% /dev/shm
   
   2020-10-27 15:15:35
   tmpfs 2018788 0 2018788 0% /sys/fs/cgroup
   
   2020-10-27 15:15:35
   fs-xxxxxxxx.efs.us-east-1.amazonaws.com:/ 9007199254739968 0 9007199254739968 0% /Any_Container_Path
   
   2020-10-27 15:15:35
   /dev/xvdcz 30832548 9859324 19383976 34% /etc/hosts
   
   2020-10-27 15:15:35
   tmpfs 2018788 0 2018788 0% /proc/acpi
   
   2020-10-27 15:15:35
   tmpfs 2018788 0 2018788 0% /sys/firmware
   
   2020-10-27 15:15:35
   tmpfs 2018788 0 2018788 0% /proc/scsi
   
   RUNNING

Related information

Security and access controls for Amazon EFS volumes

Specify an Amazon EFS file system in an Amazon ECS task definition

Configuring Amazon EFS file systems for Amazon ECS using the console