Cisco Cisco Administrative Workstation Installation Guide

High Availability with IPCC Express Gateway

In high availability, there is a Side A PG installed on each of the two nodes of CRS. Only one
of the servers, the Master, is active at a time. When the active side fails, the standby side starts
up, but all the calls in queue are dropped and the now-active server and PGs go through a full
re-initialization. (For more information on the CRS Master Server, see the Cisco CRS
Administration Guide.)

The following figure shows an IPCC Gateway Express PG on two CRS Servers, the master and
the standby servers.

Figure 17: High Availability with IPCC Express Gateway PG

Only the IPCC Express Gateway PG on the Master CRS node is activated and connects to the
Unified ICME CallRouter; the IPCC Gateway Manager controls activation and deactivation of
the IPCC Express Gateway PG.

When there is a Mastership change (failover) on the Unified CCX servers, the PGs on both
nodes are notified of the change; and activate or deactivate according to their Mastership status.

The Unified CCX child still maintains its site or local routing capability. In contrast to Unified
CCE deployments where CallManager PG loses contact with the CallRouter, Unified CCX is
self-sustaining and does not need Unified ICME to function.

Cisco IPCC Gateway Deployment Guide for Unified ICME, Unified CCE, and Unified CCX, Enterprise Releases 7.2(1) and Express Release 5.0(1)