mongodb://<user>:<password>@staff.mongohq.com:10022/testdb

my $connection = MongoDB::Connection->new(host => 'localhost', port => 27017);
my $database   = $connection->foo;

my $connection = MongoDB::Connection->new(host => 'mongodb://staff.mongohq.com:10022', username => 'dbuser', password => 'dbpass', db_name => 'testdb');
my $database = $connection->testdb;

use MongoDB;
use MongoDB::OID;

my $conn = MongoDB::Connection->new(
    host => 'remote server's inet address or host name',
    port => 27017,
    username=>'your_user_name',
    password => 'your_password',
    db_name => 'your_db_name'
);