How to Resolve the \'No Reachable Server\' Error When Connecting to MongoDB Atlas with Go\'s mgo Driver?

Connecting to MongoDB Atlas with Go mgo: Resolving "No Reachable Server" Issue

When attempting to connect to a MongoDB Atlas replica set using the mgo driver for Go, you may encounter the persistent error "no reachable server." This issue can arise even if you can successfully connect with other languages using the same connection string.

The root cause of this problem often lies in missing or incorrect configuration of SSL connection parameters. To establish a secure connection with MongoDB Atlas, you must use a TLS configuration. Here's a code snippet that demonstrates how to configure your connection for SSL:

package main

import (
    "gopkg.in/mgo.v2"
    "crypto/tls"
    "net"
)

func main() {
    tlsConfig := &tls.Config{}

    dialInfo := &mgo.DialInfo{
        Addrs: []string{"prefix1.mongodb.net:27017",
            "prefix2.mongodb.net:27017",
            "prefix3.mongodb.net:27017"},
        Database: "authDatabaseName",
        Username: "user",
        Password: "pass",
    }
    dialInfo.DialServer = func(addr *mgo.ServerAddr) (net.Conn, error) {
        conn, err := tls.Dial("tcp", addr.String(), tlsConfig)
        return conn, err
    }
    session, err := mgo.DialWithInfo(dialInfo)
    if err != nil {
        // Handle error
    }

    // Use the session to interact with MongoDB Atlas
}

Alternative Solution:

Another option is to use the ParseURL method to parse the MongoDB Atlas URI string. However, this method does not currently support SSL (mgo.V2 PR:304). A workaround is to remove the "ssl=true" line from the URI before parsing.

// URI without ssl=true
mongoURI := "mongodb://username:[email protected],prefix2.mongodb.net,prefix3.mongodb.net/dbName?replicaSet=replName&authSource=admin"

dialInfo, err := mgo.ParseURL(mongoURI)

// Below part is similar to the previous example.
// ... (remainder of code)

By following these steps, you can successfully connect to MongoDB Atlas using the mgo driver and resolve the "no reachable server" issue.

The above is the detailed content of How to Resolve the \'No Reachable Server\' Error When Connecting to MongoDB Atlas with Go\'s mgo Driver?. For more information, please follow other related articles on the PHP Chinese website!