Elastic Beanstalk 環境のアプリケーションディレクトリに Amazon EFS ボリュームをマウントする方法を教えてください。

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Solution stack             Application directory                    Staging directory
Nodejs                     /var/app/current                         /tmp/deployment/application
PHP                        /var/app/current                         /var/app/ondeck
Ruby (Passenger)           /var/app/current                         /var/app/ondeck
Ruby (Puma)                /var/app/current                         /var/app/ondeck
Java with Tomcat           /usr/share/tomcat*/webapps/ROOT          /tmp/deployment/application/ROOT
Java SE                    /var/app/current                         /var/app/staging
Python                     /opt/python/current/app                  /opt/python/ondeck/app
Go                         /var/app/current                         /var/app/staging
Single Container Docker    /var/app/current                         /var/app/staging
Multi-Container Docker     /var/app/current                         /var/app/staging
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===============================
[2020-02-12T02:28:18.237Z] INFO  [3159]  - [Application deployment Sample Application@1/StartupStage1/AppDeployEnactHook/01_flip.sh] : Starting activity...
[2020-02-12T02:28:18.431Z] INFO  [3159]  - [Application deployment Sample Application@1/StartupStage1/AppDeployEnactHook/01_flip.sh] : Completed activity. Result:
  ++ /opt/elasticbeanstalk/bin/get-config container -k app_staging_dir
  + EB_APP_STAGING_DIR=/var/app/ondeck
  ++ /opt/elasticbeanstalk/bin/get-config container -k app_deploy_dir
  + EB_APP_DEPLOY_DIR=/var/app/current
  + '[' -d /var/app/current ']'
  + mv /var/app/current /var/app/current.old
  + mv /var/app/ondeck /var/app/current
  + nohup rm -rf /var/app/current.old
===============================

===============================
[2020-02-12T02:28:16.336Z] INFO  [3159]  - [Application deployment Sample Application@1/StartupStage0/AppDeployPreHook/01_unzip.sh] : Starting activity...
[2020-02-12T02:28:16.631Z] INFO  [3159]  - [Application deployment Sample Application@1/StartupStage0/AppDeployPreHook/01_unzip.sh] : Completed activity. Result:
  ++ /opt/elasticbeanstalk/bin/get-config container -k app_user
  + EB_APP_USER=webapp
  ++ /opt/elasticbeanstalk/bin/get-config container -k app_staging_dir
  + EB_APP_STAGING_DIR=/var/app/ondeck
  ++ /opt/elasticbeanstalk/bin/get-config container -k source_bundle
  + EB_SOURCE_BUNDLE=/opt/elasticbeanstalk/deploy/appsource/source_bundle
  + rm -rf /var/app/ondeck
  + /usr/bin/unzip -d /var/app/ondeck /opt/elasticbeanstalk/deploy/appsource/source_bundle
  Archive:  /opt/elasticbeanstalk/deploy/appsource/source_bundle
     creating: /var/app/ondeck/.ebextensions/
    inflating: /var/app/ondeck/.ebextensions/logging.config  
    inflating: /var/app/ondeck/scheduled.php  
    inflating: /var/app/ondeck/index.php  
    inflating: /var/app/ondeck/cron.yaml  
    inflating: /var/app/ondeck/styles.css  
   extracting: /var/app/ondeck/logo_aws_reduced.gif  
  + chown -R webapp:webapp /var/app/ondeck
  + chmod 775 /var/app/ondeck
===============================

container_commands:
  01_symlink:
    command: ln -s /efs /var/app/ondeck/

files:
  "/opt/elasticbeanstalk/hooks/appdeploy/post/01_create_symlink.sh" :
    mode: "000755"
    owner: root
    group: root
    content: |
      #!/bin/sh
      ln -s /efs /var/app/current/