I explained the experiments that you would do to figure that out: you modify parts of the system, and check if and how much that affects the consciousness. Paint the interconnects a different color: probably won't affect it. Replace the interconnect protocol with a different one: probably will have some effect. So, the paint on the interconnect: not a part of the consciousness. The interconnect protocol: part of the consciousness. If we are convinced that this is a real consciousness and thus these experiments are immoral, we simply wait until accidents naturally occur and draw conclusions from that, just like we do with human consciousness.

Of course, "the consciousness" is a nebulous concept. It would be like asking "which part of my processor is Windows" to some extent. But it's still fair to say that Windows is contained within my computer, and that the metal framing of the computer is not part of Windows.

>Is is the cluster that is conscious? Or the individual machines, or the chips, or the algorithm, or something else?

The bound informational dynamic that supervenes on the activity of the individual units in the cluster. What people typically miss is that the algorithm when engaged in a computing substrate is not just inert symbols, but an active, potent causal/dynamical structure. Information flows as modulated signals to and from each component and these signals are integrated such that the characteristic property of the aggregate signal is maintained. This binding of signals by the active interplay of component signals from the distributed components realizes the singular identity. If there is consciousness here, it is in this construct.