This document describes the CCB trunk validation parameter which is configured in the Ingress gateway.
Cisco recommends that you have knowledge of these topics:
The information in this document is based on CVP 9.0(1)
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
CVP Reporting server does not use the trunk value specified in the survivability.tcl script configured in the ingress gateway, when validating the exceeding capacity for CCB for calls that originated in the specific ingress gateway.
When CCB is implemented in a contact center environment, a callback is offered to the customer, if the call passes the validation process. In this validation process, there are several parameters from which the call will be validated.
In order for a callback to work, the correct survivability.tcl script must be running on the ingress gateway and specific parameters need to be configured under the survivability.tcl service. Therefore if for example, the caller is an IP-originated caller direct into CVP from CUCM, callback can't work. A probe is sent back to the ingress gateway according to survivability.tcl in order to check that the ingress gateway is capable of callbacks.
Under the survivability service the following parameters must be added for the call to pass validation:
param ccb id:<host name or ip of this gateway>;loc:<location name>;trunks:<number of callback trunks>
id: A unique identifier for this gateway and is logged to the database to show which gateway processed the original callback request.
loc: An arbitrary location name specifying the location of this gateway.
trunks: The number of DS0's reserved for callbacks on this gateway. Limit the number of T1/E1 trunks to enable the system to limit the resources allowed for callbacks
Before CVP version 10.5, Trunk size configured for CCB was not used in the validation of capacity for call backs on specific ingress gateway.
The existing CCB trunks parameter under the Survivability.tcl script service configured on the ingress gateway is now compared to the current calls in pending, progress, tentative or completed state with cause id connected.
Basically the process first determines the number of calls from the Callback_current table with EventTypeID in (21,22,23); Pending, Inprogress, Tentative for specific gateways.
Second, from the same Callback_current table, determine, the number of calls completed with cause connected: EventTypeID = 24 (Completed), and CauseID = 27 (Connected).
Finally the process adds these two values and compares with the number of trunks configured under the Survivability.tcl service.
If the result is over the trunks threshold configured, the process sends back a failure (return 1), otherwise sends back ok (return 0).
Note: this problem is related to the CDETS: CSCue59908 - CVP does not use the gateway trunk size to validate CallBack Capacity