PM2 cheatsheet

The latest PM2 version is installable with NPM or Yarn

$ npm install pm2@latest -g

OR

$ yarn global add pm2

The simplest way to start, daemonize and monitor your application is by using this command line

$ pm2 start app.js

Or start any other application easily

$ pm2 start bashscript.sh
$ pm2 start python-app.py --watch
$ pm2 start binary-file -- --port 1520

Specify an app name

--name <app_name>

Watch and Restart app when files change

--watch

Set memory threshold for app reload

--max-memory-restart <200MB>

Specify log file

--log <log_path>

Pass extra arguments to the script

-- arg1 arg2 arg3

Delay between automatic restarts

--restart-delay <delay in ms>

Prefix logs with time

--time

Do not auto restart app

--no-autorestart

Specify cron for forced restart

--cron <cron_pattern>

Attach to application log

--no-daemon

Managing application state is simple here are the commands

$ pm2 restart app_name
$ pm2 reload app_name
$ pm2 stop app_name
$ pm2 delete app_name

Instead of app_name you can pass:

all to act on all processes

id to act on a specific process id

Now that you have started this application, you can check its status, logs, metrics and even get the online dashboard with pm2.io.

List the status of all application managed by PM2

$ pm2 [list|ls|status]

To display logs in realtime

$ pm2 logs

To dig in older logs

$ pm2 logs --lines 200

Here is a realtime dashboard that fits directly into your terminal

$ pm2 monit

Web based dashboard, cross servers with diagnostic system

$ pm2 plus

For Node.js applications, PM2 includes an automatic load balancer that will share all HTTP[s]/Websocket/TCP/UDP connections between each spawned processes.

To start an application in Cluster mode

$ pm2 start app.js -i max

Read more about cluster mode here.

You can also create a configuration file, called Ecosystem File, to manage multiple applications. To generate an Ecosystem file

$ pm2 ecosystem

This will generate an ecosystem.config.js file

module.exports = {
  apps : [{
    name: "app",
    script: "./app.js",
    env: {
      NODE_ENV: "development",
    },
    env_production: {
      NODE_ENV: "production",
    }
  }, {
     name: 'worker',
     script: 'worker.js'
  }]
}

And start it easily

$ pm2 start ecosystem.config.js

Read more about application declaration here

Restarting PM2 with the processes you manage on server boot/reboot is critical. To solve this, just run this command to generate an active startup script

$ pm2 save

Read more about startup script generator here

It’s pretty easy with the --watch option

$ cd /path/to/my/app
$ pm2 start env.js --watch --ignore-watch="node_modules"

This will watch & restart the app on any file change from the current directory + all subfolders and it will ignore any changes in the node_modules folder --ignore-watch="node_modules".

You can then use pm2 logs to check for restarted app logs.

We made it simple, there is no breaking change between releases and the procedure is straightforward

$ npm install pm2@latest -g

Then update the in-memory PM2

$ pm2 update