The host should be your Recording Server(s), not Management server. The Management Server might share the physical server with a Recording Server, but especially in larger installations it will not, at any rate with multiple Recording Servers there will be multiple host addresses.
When you get the configuration from the Management Server it will include the Recording Server hosts. Use ServerComandService.GetConfiguration
TCP Video Viewer (and ServerCommandWrapper) sample might be helpful for you to see how to login and how to use GetConfiguration from ServerCommandService.