How to call a gen_server from another node?

[ulrika@REDACTED]

I have a gen_server question that I hope somebody could help me with.

I'm developing a remote debugging feature to use in a test environment
where we're running the same application on several computers. The idea is
to be able to debug these machines locally by using a macro, which sends a
message to the user/s who listens to that specific machine, via a server
program on a specific "debug node". So there's the application running on
several nodes, the debug node and a node on the local host.
I have a fully functional program now, but I'm using a simple server -
i.e. I have written a receive loop, which captures the messages sent via
the macro and then distributes them to the correct local hosts.

Is it possible to use a gen_server instead? How do I send a message from a
macro on one node to a gen_server process on another/call a function in
some other program on another node?

I'm sending messages to the server like this (using the macro):
{ProcessName, Node} ! Msg


Thanks for help,
Ulrika