5 dual speed hubs are connected; one novell file server (4.11) is connected to one hub, 17 PC's are connected to the same hub; when all 5 hubs are connected (over cascade cables), the PC's will hang when running a special software which is sending a lot of broadcasts. If I disconnect 4 hubs and run that software, there is no problem. As I see there is no second connection between 2 hubs over the RJ45 ports.<br>My question now is: which tool (hardware/software) can I use to determine, what is going wrong if all hubs are connected. <br>Or has anybody another idea how to find the problem ?