LoggerNet can be configured to have two paths to a datalogger, simply by entering the datalogger twice in the network map with different comms links. LoggerNet, however, treats them as separate entities, so it will try to collect all the data twice via the two separate paths if both are enabled. Some users have set this up where they use one route most often, and manually enable collection to the backup route if the main link is lost.
An alternative to this scheme is to set up the backup route but not add the datalogger. Then, if the main link to the datalogger goes down, simply drag-and-drop the datalogger to the backup route. After the main link is working again, the datalogger can be moved again. This keeps data collection pointers for that datalogger intact.