Cisco Cisco Customer Voice Portal 8.0(1) Design Guide

If your Unified CVP Call Server, Media Server, and Unified CVP VXML Server reside on the same 
hardware server and you have multiple co-resident servers, Unified CVP will not automatically use the 
same physical server for call control, VXML, and media file services. Just because the components are 
co-resident, that does not force one component to use the other co-resident components, and it is just as 
likely to use the components located on another server.

By default, the components are load-balanced across all of the physical servers and do not attempt to use 
the same server for all of the services. Over the course of thousands of calls, all of the components on 
all of the servers will be load-balanced and equally utilized, but for one particular call it is possible to 
be using several different physical servers. Because of this, for one particular call you can be using 
H.323/SIP call control on one server, VoiceXML on another server, and the media files on yet another 
server.

You can simplify management and troubleshooting by configuring Unified CVP to use the same physical 
server for all of these functions on a per-call basis. Of course, if there is only one server in the system, 
then this is not a concern. The instructions below show you how to configure Unified CVP so that it does 
use components on the same physical server instead of load-balancing and using a random server for 
each component.

Perform the following steps to choose the co-resident Unified CVP VXML Server in the ICM Script 
Editor:

When setting up the media_server ECC variable that specifies your Unified CVP VXML Server in 
the ICM script, use the Formula Editor to set the media_server ECC variable to 
concatenate("http://",Call.RoutingClient,":7000/CVP"), where Call.RoutingClient is the 
built-in call variable that ICM sets automatically for you. The routing client name in ICM is not 
necessarily the same as the Unified CVP Server's hostname (and usually is not the same).

You can then use the routing client name as a hostname in the VXML gateway. However, do not use 
non-compliant characters such as an underscore as part of the hostname because the router cannot 
translate the hostname to an IP address if it contains any non-complaint characters. Cisco also 
recommends using the ip hostname strict command in the router to prevent the use of invalid 
characters in the hostname. This will ensure that the hostname is acceptable to Unified CVP.

Configure the routing client hostname for every Unified CVP Server Routing Client.

Perform the following steps to choose the co-resident Media Server in Cisco Unified Call Studio:

In the ICM script, set one of the ToExtVXML[] array variables with the call.routingclient data, such 
as "ServerName=call.routingclient." This variable will be passed to the Unified  CVP VXML  Server, 
and the variable will be stored in the session data with the variable name ServerName.

In Cisco Unified Call Studio, use a substitution to populate the Default Audio Path. Add the 
Application_Modifier element found under the Context folder, and specify the Default Audio Path 
under the Settings tab in the following format:

http://{Data.Session.ServerName}

If you are using Micro-Apps in conjunction with the Unified CVP VXML Server, you will have to pay 
careful attention to the media_server ECC variable in the ICM script because the same variable is used 
to specify both the Unified CVP VXML Server and the media server, but the contents of the variable 
uses a different format depending on which server you want to specify. The media_server ECC variable