The superserver port is recorded in the cache.cpf file, and I think it can be changed there by simply editing the file and then restarting Cache.

I'm guessing that the Cache installer uses the registry to discover the locations of the CPF files it needs to check when picking a "free" port to offer as the superserver port for a new instance. So if one of your instances wasn't properly registered at the time you installed another instance then the installer may have defaulted to a port that was actually already taken.

There's some documentation here.

In your case it sounds like a Cache instance was moved onto the server but not added to the registry that Cache's ccontrol command uses. On Windows I think Cache uses the Windows Registry. On other platforms it uses a file, and offers commands ccontrol create, ccontrol update and  ccontrol delete to maintain entries in this registry.

Alex, if you code it as an instance method (private or public) then you won't be able to call it from a classmethod (private or public) unless the caller has (or creates) an instance of its class. In other words, the decision about whether to code an instance method or a classmethod is surely independent of the decision about whether to mark that method private or public, no?

OK, I've just seen your version info in a comment on another answer.

Given you're using accessing port 80 on server xyz.x.edu I assume a regular webserver (e.g. IIS or Apache) has been set up on that server and the CSP Web Gateway added to it, then configured to connect to an InterSystems instance (perhaps on the same server, or perhaps elsewhere).

In that case, is your webserver set up to dispatch /api/atelier to the 2017.1 instance?