The build server is a one-box Dynamics 365 for Operations virtual machine, usually with demo data that is only ever used to produce builds. Even though it has data, and seems to have an application running in IIS, it cannot be used.
If we are creating a build server for a customer implementation project, most of the work is done for us. You will just need to specify the Agent Queue that we created in the previous recipe. This recipe will follow the ISV scenario where we may install the build agent ourselves.