MongooseServerSelectionError：连接 ECONNREFUSED::1:27017

Question

I have a problem when I try to connect my app with my database with Mongoose. Already tried following solutions that I found on google:

• restarting MongoDB service on windows
• manually open db with cmd located on bin file of mongodb

But I can't solve it. Can anyone help me?

//my connection
const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/notes-db-app',{
    useNewUrlParser: true, 
    useUnifiedTopology: true
})
.then(db => console.log('DB is connected'))
.catch(err => console.log(err));

And throw's me, this error

MongooseServerSelectionError: connect ECONNREFUSED::1:27017 at NativeConnection.Connection.openUri (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\connection.js:797:32) at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:330:10 at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:32:5 at new Promise () at promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:31:10) at Mongoose._promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:1151:10) at Mongoose.connect (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:329:20) at Object. (C:\Users\ivan\Desktop\NodeJS\notes-app\src\db.js:3:10)
at Module._compile (node:internal/modules/cjs/loader:1095:14) at Object.Module._extensions..js (node:internal/modules/cjs/loader:1147:10) {
reason: TopologyDescription { type: 'Unknown', servers: Map(1) { 'localhost:27017' => [ServerDescription] }, stale: false, compatible: true, heartbeatFrequencyMS: 10000, localThresholdMS: 15, logicalSessionTimeoutMinutes: undefined } }

I try to put the port on my connection code like this

//my connection
const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/notes-db-app',{
    useNewUrlParser: true, 
    useUnifiedTopology: true
})
.then(db => console.log('DB is connected'))
.catch(err => console.log(err));

and it throw's me another error

MongooseServerSelectionError: Invalid message size: 1347703880, max allowed: 67108864 at NativeConnection.Connection.openUri (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\connection.js:797:32) at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:330:10 at C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:32:5 at new Promise () at promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\helpers\promiseOrCallback.js:31:10) at Mongoose._promiseOrCallback (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:1151:10) at Mongoose.connect (C:\Users\ivan\Desktop\NodeJS\notes-app\node_modules\mongoose\lib\index.js:329:20) at Object. (C:\Users\ivan\Desktop\NodeJS\notes-app\src\db.js:3:10)
at Module._compile (node:internal/modules/cjs/loader:1095:14) at Object.Module._extensions..js (node:internal/modules/cjs/loader:1147:10) {
reason: TopologyDescription { type: 'Unknown', servers: Map(1) { 'localhost:3000' => [ServerDescription] }, stale: false, compatible: true, heartbeatFrequencyMS: 10000, localThresholdMS: 15, logicalSessionTimeoutMinutes: undefined } }

Answer 1

const uri = 'mongodb://localhost:27017/test';

const options = {
    useNewUrlParser: true,
    useUnifiedTopology: true,
    serverSelectionTimeoutMS: 5000,
    autoIndex: false, // Don't build indexes
    maxPoolSize: 10, // Maintain up to 10 socket connections
    serverSelectionTimeoutMS: 5000, // Keep trying to send operations for 5 seconds
    socketTimeoutMS: 45000, // Close sockets after 45 seconds of inactivity
    family: 4 // Use IPv4, skip trying IPv6
}

const connectWithDB = () => {
    mongoose.connect(uri, options, (err, db) => {
      if (err) console.error(err);
      else console.log("database connection")
    })
}

connectWithDB()

Answer 2

I finally solved it.

Enabling the IPV6 that MongoDB has disabled by default. Using the following command line on CMD:

mongod --ipv6 

And then try again the connection and it works!

const mongoose = require('mongoose');

mongoose.connect('mongodb://localhost/notes-db-app',{
    useNewUrlParser: true, 
    useUnifiedTopology: true
})
.then(db => console.log('DB is connected'))
.catch(err => console.log(err));

_{Posted on behalf of the question asker}

Answer 3

Simply pass third parameter family:4 ie.

mongoose.connect('mongodb://localhost/notes-db-app',{
    useNewUrlParser: true, 
    useUnifiedTopology: true,
    family: 4,
})

Answer 4

If the Error states:

connect() Error :MongooseServerSelectionError: connect ECONNREFUSED ::1:27017

Then the connection to localhost is refused on the IPv6 address ::1 . Mongoose per default uses IPv6 ..

For a quick check you can set the IPv4 address explicit:

 mongoose.connect('mongodb://127.0.0.1/test')

Answer 5

Probably the hostname/IP of the server to which you want to connect is not correctly set.
I'm used to see that error as:

MongooseServerSelectionError: connect ECONNREFUSED <hostname/hostIP>:<port>

and in the console log you've posted, the <hostname/hostIP> part is malformed/missing.

Example - for a mongodb server running locally on port 27017 this is the error when server is down:

MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017

If you're using mongodb URI to connect to the db make sure that it looks like this

"mongodb://<hostname/hostIP>:<port>"

Answer 6

1. Open your terminal and type this command: mongod
2. Then use your app.js to establish a connection by writing this code :

    const mongoose=require("mongoose"); mongoose.connect('mongodb://localhost/notes-db-app',{ useNewUrlParser: true, useUnifiedTopology: true, family: 4, })

3. It's done now. Simply open your mongo shell or your mongodb compass and look for whatever you have added.

Answer 7

Problem is, the localhost alias resolves to IPv6 address ::1 instead of 127.0.0.1

However, net.ipv6 defaults to false .

The best option would be to start the MongoDB with this configuration:

net:
  ipv6: true
  bindIpAll: true

or

net:
  ipv6: true
  bindIp: localhost

Then all variants should work:

C:\>mongosh "mongodb://localhost:27017" --quiet --eval "db.getMongo()"
mongodb://localhost:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.0

C:\>mongosh "mongodb://127.0.0.1:27017" --quiet --eval "db.getMongo()"
mongodb://127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.0

C:\>mongosh "mongodb://[::1]:27017" --quiet --eval "db.getMongo()"
mongodb://[::1]:27017/?directConnection=true&appName=mongosh+1.6.0

If you don't run MongoDB as a service then it would be

mongod --bind_ip_all --ipv6 <other options>

NB, I don't like configuration

net:
  bindIp: <ip_address>

in my opinion this makes only sense on a computer with multiple.network interfaces. Use bindIp: localhost if you need to prevent any connections from remote computer (eg while maintenance or when used as backend database for a web-service), otherwise use bindIpAll: true

Answer 8

Use this at the beginning of your code:

const dns = require('dns');

// Set default result order for DNS resolution
dns.setDefaultResultOrder('ipv4first');

Answer 9

Is MongoDB running on PORT 27017? Make sure it's running on the specified PORT. See if it solves your problem. Also check your credentials: Mongo username and password.

It would have been more helpful if you had posted your source code for database connection.

Answer 10

I also faced the same problem those commands worked for me(Ubuntu machine)

sudo chown -R mongodb:mongodb /var/lib/mongodb
sudo chown mongodb:mongodb /tmp/mongodb-27017.sock

Then

sudo service mongod restart