pm2 start server.js

Generate Startup Script (to enable as system service)
pm2 startup

Freeze your process list across server restart
pm2 save

Remove Startup Script (to disable as system service)
pm2 unstartup

$ pm2 stop     <app_name|namespace|id|'all'|json_conf>
$ pm2 restart  <app_name|namespace|id|'all'|json_conf>
$ pm2 delete   <app_name|namespace|id|'all'|json_conf>