Normally I create a volume in the docker-compose.yml file to share data between the container and my machine. I define the durable directory in this volume, so when I restart the container I don't lose the data stored.

version: '3.6'
services:
  iris:
    build: 
      context: ./iris
      dockerfile: Dockerfile
    restart: always
    container_name: iris
    ports:
      - 51773
      - 52773:52773
      - 1972:1972
      - 53773
    volumes:
      - ./iris/data:/durable 
    environment: 
      - ISC_DATA_DIRECTORY=/durable
    networks: 
      - production-network