I have a 2 node replica set + 1 arbiter all running on Linux (RHEL 6) using SSL. Replication is working fine however I am seeing some strange errors in the Mongo log file when connecting to the replica set (or even a single node) from Node.js. Despite the log file indicating that the connection has been closed, I am able to run queries on the DB without issue, it's just that the log file is filling up with the messages (about once ever 5 seconds).

Code:

var MongoClient = require('mongodb').MongoClient;

MongoClient.connect('mongodb://username:password@server1:1234,server2:1234/dbname?ssl=true&authSource=admin&replicaSet=rs0', function(err, db) {
    if(err) {
    	console.log(err);
    }
    else {
    	console.log('Connected to mongo');
    }
});

Log:

Wed Dec  4 07:59:23.044 [conn1450298] ERROR: error:140760FC:SSL routines:SSL23_GET_CLIENT_HELLO:unknown protocol
Wed Dec  4 07:59:23.044 [conn1450298] SocketException handling request, closing client connection: 9001 socket exception [6]

I don't see the same when connecting from a Java process so I'm assuming that the issue here is in he client code rather than the MongoDB setup.

Thanks

Steve