Cisco Cisco Unified Contact Center Management Portal 8.5(2) Leaflet

Figure 3-18 shows a CTI Manager service failure on Unified CM subscriber C that is used to 
communicate with the Unified CCE PG. The CTI Manager services are running on all the Unified CM 
subscribers in the cluster, but only subscribers C and D are configured to connect to the Unified CCE 
PGs. During this failure, the PG will detect the loss of the JTAPI connection and fail-over to the 
redundant/duplex PG side. 

The following conditions apply to this scenario: 

All phones and gateways are registered with Unified CM subscriber A. 

All phones and gateways are configured to re-home to Unified CM subscriber B (that is, B is the 
backup server). In this case they will not re-home because subscriber A is still functional. 

Unified CM subscribers C and D are each running a local instance of CTI Manager and are designed 
to connect to the Unified CCE PGs. 

If the Unified CM CTI Manager service on subscriber C fails, the PG side A detects a failure of the 
CTI Manager service and induces a failover to PG side B. 

PG side B registers all dialed numbers and phones with the Unified CM CTI Manager service on 
subscriber D, and call processing continues. 

Agents with calls in progress will stay in progress, but with no third-party call control (conference, 
transfer, and so forth) available from their agent desktop softphones. After an agent disconnects 
from all calls, that agent's desktop functionality is restored. Although the call stays active, Unified