A timeout occured after 30000ms selecting a server using CompositeServerSelector

Question

I try to deploy my Mongo database in Mongolabs, everything works fine, and I create a new database. Please see my connectionstring.

    public DbHelper()
    {

        MongoClientSettings settings = new MongoClientSettings()
        {
            Credentials = new MongoCredential[] { MongoCredential.CreateCredential("dbname", "username", "password") },
            Server = new MongoServerAddress("ds011111.mongolab.com", 11111),
            //ConnectTimeout = new TimeSpan(30000)
        };

        Server = new MongoClient(settings).GetServer();

        DataBase = Server.GetDatabase(DatabaseName);

    }

but when I try to connect the database it's shows error like:

Answer 1

Add "?connect=replicaSet" to the end of your connection string if connecting to MongoLab.

new MongoClient("mongodb://username:[email protected]:11111/db-name?connect=replicaSet")

This JIRA ticket has some details: https://jira.mongodb.org/browse/CSHARP-1160

Basically the default is to connect to a replica set member. But MongoLab's Single-Node settings are actually a single node replica set and this causes us to not trust it. Appending ?connect=replicaSet to your connection string will force the driver to move into replica set mode and all will work.

Found that info here.