Can't connect to MongoDB 6.0 Server locally using Node.js driver

Question

I have just started learning about MongoDB and I am trying to host my Node.js application locally via MongoDB Server 6.0 (without using Mongoose or Atlas).

I copied the async JavaScript code given in the MongoDB documentation. I made sure to run mongod before executing the below code:

MongoDB server started

const { MongoClient } = require("mongodb");

// Connection URI
const uri =
  "**mongodb://localhost:27017**";

// Create a new MongoClient
const client = new MongoClient(uri);

async function run() {
  try {
    // Connect the client to the server (optional starting in v4.7)
    await client.connect();

    // Establish and verify connection
    await client.db("admin").command({ ping: 1 });
    console.log("Connected successfully to server");
  } finally {
    // Ensures that the client will close when you finish/error
    await client.close();
  }
}
run().catch(console.dir);

It's throwing an error:

Answer 1

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 will work:

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

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

C:\>mongosh "mongodb://%COMPUTERNAME%:27017" --quiet --eval "db.getMongo()"
$ mongosh "mongodb://$HOSTNAME:27017" --quiet --eval "db.getMongo()"
mongodb://******: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. However, since MongoDB does not support multiple interfaces it does not make much sense either. Also depending on your network settings, this IP may change at any time.

Use bindIp: localhost if you like to permit connections only from the local machine, e.g. while maintenance or when used as backend database for a web-service. Use bindIpAll: true if you like to permit connections also from remote machines.

Answer 2

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

From @Wernfried Domscheit Answer above. The summary for me

I just replace mongodb://localhost/dbName with mongodb://127.0.0.1:27017/dbName and it worked.

Answer 3

Use this if you are using the node version 18(Ig it also works for 17)

mongoose.connect("mongodb://127.0.0.1:27017/newdb", {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});
var db = mongoose.connection;

db.on("error", () => console.log("error connecting to database"));

db.once("open", () => console.log("Connected to database"));

Answer 4

You can try this:

mongoose.connect("mongodb://0.0.0.0:27017").then(() => {
  console.log("database connected)).catch((err) => {
  console.log("error while connecting to database")
})