Oooh, interesting. Although I'm not entirely sure this is what I need.
The reason why we wish to have a hobbit (sorry, xymon..I'm still used to the old name!) in each data centre is in case our inter-data centre links go down.
For example, currently we only have a xymon server at site B. If the link between A and B went down, we would suddenly have no visibility of any clients in site A. Therefore we wish to have xymon servers in site A, B and C monitoring local clients to that data centre. The issue is that we do not want to have to view 3 separate xymon server pages to see the status overall, hence why I wan't all three to communicate to each other. So Xymon A can send A results to B and C, Xymon B can send B results to A and C etc.
Is this possible? I can't immediately see a way to do this with a proxy, as it just seems to be adding another layer, that would still have to send out results to all 3 xymons (so brings me back to the original situation of having each client send to all 3 xymons anyway, which is something we don't really want to do).