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VVB load balancing to ASR/TTS servers


We are migrating from VXML Gateway to Virtual Voice Browsers in our UCCE environment utilizing CVP VXML applications.  Currently we utilize a virtual IP (VIP) to load balance the ASR/TTS requests from VXML Gateway to multiple Nuance Recognizer servers.  With VVB, we are able to list multiple ASR and TTS servers in the web interface that will be round robin routed to per our understanding.  Is anyone utilizing a VIP to load balance to speech recognition servers when they are using VVB?  Is it recommended to eliminate the VIP and let VVB handle load balancing and failover (we see reachable/unreachable states when Nuance servers are online/offline accordingly)?

6 Replies 6

Omar Deen
I recently seen it done where the customer has a VIP for everything. So in your case, you can round robin your ASR and TTS VIPs. There's not recommendation one way or another.

VIP Advocate VIP Advocate
VIP Advocate

Yeah I've seen the same with using a VIP with VVB. The customer's reason was to allow them to only change the load balancer when they wanted to do work on specific servers. This was easier through the load balancer than having to go to VVB.



I know this is an older thread but we recently deployed this as well and using a VIP in VVB is showing unreachable on port 5060...using MRCPv2. Directly defining the hosts works fine. Are there other ports (using Vocalizer only) that are needed?  From the VVB screen only port 5060 is shown so that is what I have going through the VIP.  I see the following port usage for Speech Server located here but those other ports seem to be used for internal communication.


Unrelated, does VVB use the first server in the TTS speech server list?  Assuming so, since people are putting VIPs in place but Nuance was unable to tell me.



What's the VVB version?



David, we are currently on 11.6 and are at the very beginning of upgrading to 12.6.

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