How do I configure my Firewall for Raidar?

At the end of this ancient locked thread - http://www.readynas.com/forum/viewtopic.php?p=86947 - the solution was almost provided by nitro.

Raidiator in the ReadyNAS box talks back to RAIDar using UDP on a pseudo-random ephemeral port. nitro suggested opening an inbound UDP port range 30000 to 60000. I tried that and it didn't work for me. However, looking at the firewall logs showed that my NV+ and NV+ v2 were sending UDP packets to ports starting at 61311, which were being blocked. A later test showed them using a port range starting at 54911 or thereabouts.

So the correct solution is to open inbound 22081/udp (as the FAQ says), and the whole ephemeral port range: inbound 49152:65535/udp. That worked for me. I'm using IceFloor 1.3 as a frontend to the PF firewall supplied with Mac OSX Lion, by the way.

I wish there was a less sledgehammer solution! I noticed that both my NAS boxes were using the same port to try to talk back to RAIDar, even though the actual port number changed hugely between test runs. So it must be RAIDar that's generating the pseudo-random port and telling the NAS boxes to use it. If there was some way to configure RAIDar to use a more restricted port range then I wouldn't have to open such an enormous hole in my firewall.

NB: We're talking about software firewalls on the PC running RAIDar here. This has nothing to do with the firewall in your router. I'm sure forov understands that but I thought I'd make the point for the benefit of other readers.