Every device on the network has its own hostname. If you are connecting two devices together, you have two hostnames. If you are connecting three devices together, you have three hostnames. Your data flows will define which hostnames you enter and on which systems you enter them. If you need to enter two hostnames on a given system, then you will need to use that page twice to save two separate devices with two separate acronyms and two separate hostnames.
I’m not sure what’s wrong with your data. Your screenshots don’t tell me much of anything. It looks like both devices’ measurements are being archived by PPA, so all your measurements should be showing up in the TimeSeriesMeasurement table. If you’re concern is about the zeros, try querying using a different signal ID. If your concern is about the age of your timestamps, try adding
ORDER BY ID DESC to your query.