[Freeswitch-users] FS cluster and how to get sofia gateway health status?

Hi everyone, I'm setting up FS cluster In my application, I plan to use two FS server as front and four FS as backend, the incoming calls first send to the front FS, then the front FS forward the call to backend FS server by return 302 to invite message. The front FS need to known the backend FS's status, so it won't forward calls to a server if it's down. The question is, how to check the backend FS's status. As I known, fs can add gateways to sofia profile, the endpoint will check gateways's state by send ping message, I think it is the function what I need if I can get the gateways's status from fs, does someone known how to do it? or can someone give me some suggestion about how to setup FS cluster? -- Lei.Tang lei.tlfly@gmail.com