incoming load balancing

[tarikzz]

Hello,

I need to setup an incoming load balancing system able to deal with Vicidial queues.

My current architecture is simple (signature) vicibox8 (telephony+web) - with external DB server.
- incoming : 15 simultaneous calls
- outgoing : 3-5 simultaneous blind transferred calls
- G729 between the telephony server and the agents, for bandwidth purpose

With that, I often hit a glass ceiling, when having too many simultaneous incoming calls (and few outgoing) - all being recorded. A lot of bugs are occurring around 15-17 simultaneous incoming calls + few simultaneous outgoing calls, which is not surprising as it is stated in the manual.

Until now I did few things to slightly increase the capacity (less recording, setting up a dedicated DB server) ...

But finally it seems I have no other choice than scaling horizontally with at least one additional telephony server.

So here are my questions ; how can I setup a multi-telephony server (2) in the aim to load balance the incoming calls ? is OpenSIPS the more suitable choice to load balance incoming calls ? will the queue be unified (a single queue for all telephony servers, so any incoming call will go straight to the first available agent, or wait in queue until there is an available agent) ?

Currently I have trunks between my clients and an a2billing server ; a2billing server sends the incoming calls to my only telephony server (which is registered on a2billing), and all the agents are registered on the telephony server.

With the new clustered solution, I could just add an OpenSIPS server between a2billing and the 2 telephony servers ? meaning OpenSIPS server will register on a2billing, and agents will register on OpenSIPS ?
Also, is there any way to get a2billing out of the picture ? maybe OpenSIPS will have reliable billing cdrs ?

And finally, as vicibox9 has been released recently, does it worth it creating the 2 new telephony servers with vicibox9 ? (I cannot find the vicibox9 changelog)


Thank you very much for any advice you can give me on this !