So, I have a Ubuntu 16.04 server that is hosting 4 LXD containers. There are no websites associate with these containers, However each container is associated to a specific user. So when user A for instance want to use the app, I need to be able to route him to Container A.
The same for the other 3 users...B --> Container B, C --> Container C and D --> Container D. The app is an executable and functionally the same on all 4 containers. I just need the users have access to their own app.

Is nginx RP the way to go? And any comments on how to set this up?

Thanks,

Ray