I'm trying to connect to replica set from Ubuntu using this:

return when.promise(function(resolve,reject){
        new MongoClient().connect(url, {replSet: options }, function(err, db){
        console.dir(err)
        if (err)
            reject(err);

        resolve(db);
    });
});

Url looks like this:

'mongodb://mongo1.mysite.com:36108,mongo2.mysite.com:36108,mongo3.mysite.com:36108/db_config?w=0'

I'm connection to multiple databases and intermittently i see this error:

{ name: 'MongoError', message: 'no valid seed servers in list' }

And node.js crashes.

I'm kind of lost at this point. And the main problem is that it works perfectly on MAC and i see this issue only on Ubuntu. I'm on the latest mongo driver for node.js

UPDATE

I took a look at the native driver source:

http://mongodb.github.io/node-mongodb-native/core/api/replset.js.html

and found out tha error being triggered by this condition (line 987): state.initialConnectionServers == 0 && state.replState.state == CONNECTING)

Still not sure why is this happening.

Increasing the amount of file descriptors solved the issue.

On Ubuntu 12.04.5 LTS default is 1024 which is not enough.