Cisco Cisco IP Contact Center Release 4.6.1 Maintenance Manual
Figure 7: PG Fault Tolerance
The OPC processes communicate with each other via a private network connection and the
Message Delivery Service (MDS). The MDS provides a synchronizer service which combines
the input streams from the PIMs and PG Agents on both sides of the PG to ensure that both
OPC processes see exactly the same input.
Message Delivery Service (MDS). The MDS provides a synchronizer service which combines
the input streams from the PIMs and PG Agents on both sides of the PG to ensure that both
OPC processes see exactly the same input.
The OPC process is responsible for activating PIMs and PG Agents on each side of the duplexed
PG. The OPC process also supplies uniform message sets from various PG types to the Central
Controller.
PG. The OPC process also supplies uniform message sets from various PG types to the Central
Controller.
In Unified ICM, as a default, OPC does not keep calls in memory waiting to be re-initialized
upon PIM activation after a PG failover. This might result in calls having calltype, call variables
and ECC variables lost on Agent Desktops when a PG failover occurs.
upon PIM activation after a PG failover. This might result in calls having calltype, call variables
and ECC variables lost on Agent Desktops when a PG failover occurs.
The PIMs manage the interface between different types of ACDs and the OPC. PIMs are
duplicated on each side of the system and operate in hot standby mode. A PIM can be active
on either side of the duplexed PG, but not on both sides at the same time. For example, in the
figure above PIMs 1 and 2 are active on Side A; PIM 3 is active on Side B. The duplexed OPCs
communicate with each other through the MDS to ensure that a PIM is active only on one side
at a time.
duplicated on each side of the system and operate in hot standby mode. A PIM can be active
on either side of the duplexed PG, but not on both sides at the same time. For example, in the
figure above PIMs 1 and 2 are active on Side A; PIM 3 is active on Side B. The duplexed OPCs
communicate with each other through the MDS to ensure that a PIM is active only on one side
at a time.
The duplexed PG architecture protects against a failure on one side of the PG. For example, if
an adapter card controlling access to an ACD fails, a hot standby PIM can use the alternate PIM
activation path. As shown in the above figure, PIM3 has been activated from Side B of the PG.
This might be in response to an adapter failure between the Side A PIM3 and ACD3. In this
type of failure scenario, the PG is able to maintain communication with the attached ACD.
an adapter card controlling access to an ACD fails, a hot standby PIM can use the alternate PIM
activation path. As shown in the above figure, PIM3 has been activated from Side B of the PG.
This might be in response to an adapter failure between the Side A PIM3 and ACD3. In this
type of failure scenario, the PG is able to maintain communication with the attached ACD.
Only one PG Agent actively communicates with a side of the Central Controller. When messages
arrive at the Central Controller, they are delivered to both sides by the Central Controller
arrive at the Central Controller, they are delivered to both sides by the Central Controller
Administration Guide for Cisco Unified ICM/Contact Center Enterprise & Hosted Release 8.x
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Chapter 2: Fault Tolerance
Peripheral Gateways