问题:

i have already tried following solution but it is not working.

sudo forever start -c "npm start" ./

and package.json file is something like this, look at the start command: (this is not full package.json)

"name": "angular2-quickstart",
  "version": "1.0.0",
  "scripts": {
    "lite": "lite-server",
    "gulp": "gulp",
    "start": "concurrent \"npm run gulp\" \"npm run lite\" ",
    "postinstall": "typings install",
    "tsc": "tsc",
    "tsc:w": "tsc -w",
    "typings": "typings"
  },

回答1:

I'm going to piggyback off of this question, most importantly this part:

nearly every Linux distro comes with systemd, which means forever, monit, etc are no longer necessary - your OS already handles these tasks.

You can configure a service file for angular2-quickstart that your OS's systemd can use to start up a background process for your application. Here is an article on deploying applications in Linux environments that can help.