Best Practice to Configure the IP Addressing Mode for CTI Route Points and CTI Ports

Introduction

This document describes the best practices for Unified Contact Center Express (UCCX) while UCCX Computer Telephony Integration (CTI) Route Points and CTI Ports are configured.

Prerequisites

Requirements

Cisco recommends that you have knowledge of these topics:

• Applicable to all releases of UCCX 10.x, 11.x 
• Cisco Unified Communications Manager (CUCM) 11.x, 10.x and 9.x releases.

Components Used

This document is not restricted to specific software and hardware versions.

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.

Problem: Issues of Registration with UCCX Triggers and UCCX CCGs

When UCCX Triggers (CTI Route Points) and UCCX Call Control Groups(CCGs - collection of CTI Ports) are created, issues can be faced with the registration of these virtual devices.

This can affect registration and well as inbound calling capabilities (E.g Busy Tone) when calling the CTI Route Points. Issues can be faced with remote node taking calls (after an Engine failover) when the Engine on UCCX Node 2 is Master, using a different CTI Provider (i.e, another CUCM Subscriber) and the caller receives a busy tone.

Analysing the logs, you can see the issue is linked to the UCCX Java Telephony API (JTAPI) component, which communicates with a specific CTI provider. When the CTI provider is changed to a different CUCM Subscriber, the issue is resolved.

After investigation, you see that this issue is related to the registration of the entities, especially with regards to the IP addressing mode for these devices (CTI ports, Route Points).

When you add the triggers and CCGs from UCCX, the Common Device Configuration (CDC) is set None (default).

This can be seen only from the CUCM administration page.

When you use the Default CDC, the used IP addressing mode for the devices is set IPv4 and IPv6.

In CUCM 9.x especially, IPv6 addressing mode causes issues in the registration of these entities.

This is the root cause of the issue.

Recommendation

It is recommended to configure a Common Device Configuration with IP addressing mode set to IPv4 Only.

Procedure

Step 1. Login to the CUCM.

Step 2. Create an IPv4 Only CDC. Navigate to Cisco Unified CM Administration > Devices > Device Settings > Common Device Configuration. Click Add New. Give it a name, and set the IP Addressing Mode to IPv4 Only. And then Save.

Step 3. In order to assign the created CDC to your CTI Route Points and CTI ports, navigate to Cisco Unified CM Administration > Devices > CTI Route Points.

Step 4. Locate your UCCX triggers. Click on one of them.

Step 5. Change the Common Device Configuration to the one created in step 2. Save and Reset.

Step 6. Do the same for your CTI Ports. You can find your CTI ports under Device > Phone.

Note: If you wanted to apply the changes in bulk, you can utilize CUCM’s BAT Import/Export option to export the Route Points and CTI ports, modify them with the needed Common Device Configuration, then import them back.

For more info about BAT, please check the configuration guide:

• https://www.cisco.com/c/en/us/support/docs/unified-communications/bulk-administration-tool/200596-Bulk-Configure-Changes-with-Import-Expor.html
• https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/bat/11_5_1/CUCM_BK_B4FA1139_00_bulk-administration-guide_1151.html

Related defects

The following defects cover these issues, and are resolved on CUCM 11.x

CSCus44723     IP Addr Mode for a device with no Common Device Config
CSCuw60678     All CTI ports being created as IPV4 rather than IPV6