1. docker build -t nodeapp .
1. docker run --name nodeapp -p 9999(outside access):9999(inside docker) nodeapp
1. docker stop nodeapp
1. docker rm nodeapp
1. docker run -d(detach) -p 8000:9999 nodeapp
2. docker run -d(detach) -p 8001:9999 nodeapp
3. docker run -d(detach) -p 8002:9999 nodeapp
4. docker run -d(detach) -p 8003:9999 nodeapp