MongoNetworkError: connection 4 to localhost:27017 timed out

Question

I'm getting connection timeout error in my server when i deployed my application in my local machine everything is working as expected but only for few bigger database queries i'm getting this error :

{ result:
   { result:
      { MongoNetworkError: connection 4 to localhost:27017 timed out
          at Socket.<anonymous> (/caching/node_modules/mongodb-core/lib/connection/connection.js:259:7)
          at Object.onceWrapper (events.js:277:13)
          at Socket.emit (events.js:189:13)
          at Socket._onTimeout (net.js:443:8)
          at ontimeout (timers.js:436:11)
          at tryOnTimeout (timers.js:300:5)
          at listOnTimeout (timers.js:263:5)
          at Timer.processTimers (timers.js:223:10)
        name: 'MongoNetworkError',
        errorLabels: [Array],
        [Symbol(mongoErrorContextSymbol)]: {} } } }

Possible duplicate of [MongoError: connection 0 to localhost:27017 timed out](https://stackoverflow.com/questions/41394850/mongoerror-connection-0-to-localhost27017-timed-out) — Raja Sekar, Apr 15 '19 at 06:29

score 4 · Answer 1 · answered Apr 15 '19 at 06:30

The issue is your query is taking a long time to process. And mongodb has a default timeout configured. If the query takes longer than this default, it fails. Pass the required timeout as per your need to the connection parameter.

const mongoose = require('mongoose');
const option = {
    socketTimeoutMS: 30000,
    keepAlive: true,
    reconnectTries: 30000
};

mongoose.connect(mongoURI, option);

score 0 · Answer 2 · answered Apr 21 '23 at 13:33

This parameters works for me:

  const MONGO_CLIENT = new MongoClient(process.env.MONGO_DB_URI, {
    useNewUrlParser: true, // Avoid deprecation warning
    useUnifiedTopology: true, // Avoid deprecation warning
    poolSize: 10, // Maintain up to 10 socket connections, default is 5
    serverSelectionTimeoutMS: 5000, // Keep trying to send operations for 5 seconds
    socketTimeoutMS: 300000, // Close sockets after 5 minutes of inactivity

  });

MongoNetworkError: connection 4 to localhost:27017 timed out

2 Answers2