HyperDB Issues

I’m trying to setup HyperDB for failover if one DB server goes offline.

I have 2 servers defined:

$wpdb->add_database(array( ‘Host’, ‘User’,’Password’ , ‘Database’));
$wpdb->add_database(array( ‘Host2’, ‘User’,’Password’ , ‘Database’));

(If my syntax is wrong, please tell me)

I keep getting this error:

“Unable to connect to :3306 to read table ‘wp_users’ (global)”

Any suggestions?

Thanks!