socket hang up

Error: socket hang up
    at createHangUpError (_http_client.js:342:15)
    at Socket.socketOnEnd (_http_client.js:437:23)
    at emitNone (events.js:111:20)
    at Socket.emit (events.js:208:7)
    at endReadableNT (_stream_readable.js:1064:12)
    at args.(anonymous function) (/usr/lib/node_modules/pm2/node_modules/event-loop-inspector/index.js:133:29)
    at _combinedTickCallback (internal/process/next_tick.js:139:11)
    at process._tickDomainCallback (internal/process/next_tick.js:219:9)