title: Postgres Docker Container data fails to mount to local
body: <p>I'm trying to do data persistence in postgres. But when I want to mount the data folder into my local file, I get this error.</p>
  
  <pre><code>fixing permissions on existing directory /var/lib/postgresql/data ... ok
  creating subdirectories ... ok
  selecting default max_connections ... 100
  selecting default shared_buffers ... 128MB
  selecting dynamic shared memory implementation ... posix
  creating configuration files ... ok
  LOG:  could not link file "pg_xlog/xlogtemp.25" to "pg_xlog/000000010000000000000001": Operation not permitted
  FATAL:  could not open file "pg_xlog/000000010000000000000001": No such file or directory
  child process exited with exit code 1
  initdb: removing contents of data directory "/var/lib/postgresql/data"
  running bootstrap script ...
  </code></pre>
  
  <p>Here's my YAML file</p>
  
  <pre><code>version: '3.1'
  
  services:
  
    postgres:
      restart: always
      image: postgres:9.6.4-alpine
      ports:
        - 8100:5432
      volumes:
        - ./pgdata:/var/lib/postgresql/data
      environment:
        POSTGRES_PASSWORD: root
  </code></pre>
  
  <p>I'm using docker toolbox on windows. The docker machine in Virtual Box.</p>