First of all, let me commend you for being concerned with your data structures. Good data structures can make a program much simpler to understand and extend.

Anyway, I'd be inclined to do something like this:

my @clusters = (
    {
        Name => 'cluster1',
        Workers => [ qw(h1 h2 h3 h4 h5 h6) ],
        Queen => 'h7'
    },
    {
        ...
    }
);

foreach my $cluster (@clusters) {
    foreach my $worker (@{$cluster->{Workers}}) {
        handle_worker($worker, ...);
    }
    handle_queen($cluster->{Queen}, ...);
}
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This is obviously very abstract. If you want to do all the workers in parallel you could. I also don't know if "workers" and "queen" correctly describes the relationship between these servers; you could probably think of better terms.

But this kind of arrangement gives you a lot of flexibility. For example, if another kind of server gets added to the mix later, it's trivial to add processing for it.