[Serusers] ser farms / architecture

[Jev]

Hi SerUsers,

I want to try and understand the issues involved in having a farm of SER 
servers.

For shared usr_loc data service, is there another way for the servers to 
share the usr_loc datasource, besides running usr_loc dbmode at 3 and 
having all ser instances updating and querying the same DB?

I would also like to segregate my registrar server from my proxy 
machine, but I still want my registrar to see invites and byes for 
billing purposes. Basically to separate all stateful proxying and rtp 
poxying (keeping it on one or more front end servers) from my 
registrar/billing server. So far I have been playing with proxying 
REGISTER and INVITE operations from the front end server(s) to a back 
end, and attempting to do call routing at the front end.
Has anyone done something similar to this in the past? I'd be interested 
to hear peoples thoughts on this layout.

Thanks,
-Jev