So, I have some idea on what a reverse proxy does and will be using nginx (with the neat proxy manager UI) for my setup.
However, I’m not completely clear what exactly I want it to do and how I cn use it to run different services on one machine. I’m especially unclear on the ports configuration … tutorials will say things like “change the listening port to xxx for that service and to port yyy for the other service”
How does this work, which ports can I use and how do I need to configure the respective services?
I’ll provide an ELI5, though if you actually want to use it you’ll have to go beyond ELI5.
You contact a web service via a combination of IP address and port. For the sake of simplicity, we can assume that domain name is equivalent to IP address. You can then compare domain name/port with street name/street number: you need both to actually find someone. By default, some street numbers are really standard, like 443 is for regular encrypted connection. But you can have any service on any street number, it’s just less nice and less standard. This is usually done on closed networks.
Now what happens if you have a lot of services and you want all of them reachable at address 443? Well basically you are now in the same situation as a business building with a lobby. Whenever you want to contact a service, you go to 443, ask the reception what floor they are in, and they will direct you there. The reception desk is your proxy: just making sure you talk to the right people.