Cisco Unified Contact Center Enterprise Solution Reference ...

CTI OS Considerations
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Figure 3-24 Redundant CTI OS Server Processes
CTI OS Client 1
CTI OS Server A
(Active)
PG A
CTI Server A
(Active)
OPC
PIM 1 PIM 32
Cisco Unified Contact Center Enterprise 7.x SRND
Chapter 3 Design Considerations for High Availability
Scenario 1: CTI Server Side A (Active) Fails
In this scenario, CTI Server side A is co-located on PG side A, and the following events occur:
CTI Server side B detects the failure of side A and becomes active.
NodeManager restarts CTI Server side A and becomes idle.
Both CTI OS Server sides A and B drop all CTI OS client/agent connections and restart after losing
the connection to CTI Server A. At startup, CTI OS Server sides A and B stay in CONNECTING
state until they connect to CTI Server side B, and then they go to CONFIGURING state, where they
download agent and call states and configuration information. CTI OS Client connections are not
accepted by CTI OS Server A and B during CONNECTING and CONFIGURING states. When CTI
OS Server synchronizes with CTI Server, the state becomes ACTIVE and it is now ready to accept
CTI OS Client connections.
Both CTI OS Clients 1 and 2 loose connections to CTI OS Servers, and they each randomly select
one CTI OS Server to connect to. CTI OS Client 1 can be connected to either CTI OS Server A or
B, and the same is true for CTI OS Client 2. During this transition, the buttons of the CTI Toolkit
Agent Desktop will be disabled and will return to operational state as soon as it is connected to a
CTI OS.
Scenario 2: CTI Server B (Idle) Fails
In this scenario, CTI Server side B is co-located on PG side B but was not the active side. The following
events occur:
CTI Server side A stays active.
CTI OS Client 2
CTI OS Server B
(Active)
PG B
CTI Server B
(Idle)
OPC
PIM 1 PIM 32
NodeManager restarts CTI Server side B and stays idle.
Neither CTI OS Clients nor CTI OS Servers are affected by this failure.
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