docker-compose.yml

# Use root/example as user/password credentials
version: '3.1'

services:

  mongo-replica-1:
    build:
      context: .
      dockerfile: Dockerfile-configsrv
    #volumes:
    #  - ./data/config-1/mongodata:/data/db
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example
    command: --config /etc/mongod.conf

  mongo-replica-2:
    build:
      context: .
      dockerfile: Dockerfile-configsrv
    #volumes:
    #  - ./data/config-2/mongodata:/data/db
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example
    command: --config /etc/mongod.conf

  mongo-replica-3:
    build:
      context: .
      dockerfile: Dockerfile-configsrv
    #volumes:
    #  - ./data/config-2/mongodata:/data/db
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example
    command: --config /etc/mongod.conf