Cisco Cisco Unified IP Interactive Voice Response (IVR) 8.0(1) Release Note
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Cisco Unified Contact Center Express Solution Reference Network Design
Chapter 2 Cisco Unified Contact Center Express Solution Architecture for Cisco Unified Communications Manager
Cisco Unified CCX Fault Tolerance
Network Partitioning
When the network is partitioned (split into two islands), each island elects its own master. When the
partition is restored, the primary engine is always elected as the master and the other node becomes the
standby. As a result, all calls with the primary engine node remain and all calls under treatment or in
queue with the other node are dropped. This primary engine concept does not apply to the master election
process in the normal failover. It only applies to the master election after partition restoration or master
election initiated from Cisco Unified CCX Administration website.
partition is restored, the primary engine is always elected as the master and the other node becomes the
standby. As a result, all calls with the primary engine node remain and all calls under treatment or in
queue with the other node are dropped. This primary engine concept does not apply to the master election
process in the normal failover. It only applies to the master election after partition restoration or master
election initiated from Cisco Unified CCX Administration website.
Note
The primary engine is always the first node that was installed in the Cisco Unified CCX cluster and
cannot be changed.
cannot be changed.
Monitoring and Recording Redundancy
The Monitoring component is automatically installed on the Cisco Unified CCX server and should be
activated to enable agent monitoring. When deploying with high availability and agent monitoring, the
Monitoring components on each server should be activated. The two servers running the Monitoring
service are sometimes considered as one monitoring domain. When configuring a phone with SPAN port
monitoring, only one SPAN port monitoring server can be assigned to this phone.
activated to enable agent monitoring. When deploying with high availability and agent monitoring, the
Monitoring components on each server should be activated. The two servers running the Monitoring
service are sometimes considered as one monitoring domain. When configuring a phone with SPAN port
monitoring, only one SPAN port monitoring server can be assigned to this phone.
When desktop monitoring is configured, CAD forwards the RTP stream to CSD. A server running the
Monitoring component is still required for CAD to retrieve the agent phone’s MAC address from the
Cisco Unified CM. Any one of the two monitoring servers could be chosen for this purpose. If one
Monitoring components fail, desktop monitoring still works, as long as the other server running the
Monitoring component is still available in the Cisco Unified CCX cluster. It is possible to configure and
enable both SPAN port monitoring and desktop monitoring for a phone. However, only one method is
used at any time for that phone. If both SPAN port monitoring and desktop monitoring are configured
correctly, desktop monitoring is chosen. If desktop monitoring fails, SPAN port monitoring is used as a
backup. Refer the Cisco Desktop Administrator User’s Guide for more information.
Monitoring component is still required for CAD to retrieve the agent phone’s MAC address from the
Cisco Unified CM. Any one of the two monitoring servers could be chosen for this purpose. If one
Monitoring components fail, desktop monitoring still works, as long as the other server running the
Monitoring component is still available in the Cisco Unified CCX cluster. It is possible to configure and
enable both SPAN port monitoring and desktop monitoring for a phone. However, only one method is
used at any time for that phone. If both SPAN port monitoring and desktop monitoring are configured
correctly, desktop monitoring is chosen. If desktop monitoring fails, SPAN port monitoring is used as a
backup. Refer the Cisco Desktop Administrator User’s Guide for more information.
When deploying with high availability and agent call recording, the Recording components on each
server must be activated. The two physical recording servers work as a single logical recording server (a
recording domain) and recording tasks are load balanced in a round robin fashion across the two physical
Recording Servers. A Cisco Unified CCX deployment only supports one recording domain. The actual
call recordings are stored only on the disk of the physical Recording component server where the
recording task took place. Therefore, if a recording server fails, the supervisor will be unable to playback
those recordings on the failed Recording server until that Recording server is operational again.
server must be activated. The two physical recording servers work as a single logical recording server (a
recording domain) and recording tasks are load balanced in a round robin fashion across the two physical
Recording Servers. A Cisco Unified CCX deployment only supports one recording domain. The actual
call recordings are stored only on the disk of the physical Recording component server where the
recording task took place. Therefore, if a recording server fails, the supervisor will be unable to playback
those recordings on the failed Recording server until that Recording server is operational again.
The two servers where the Recording components are running also serve as a backup for each other. To
function properly during a period when one of the servers fails, the two Recording servers must be sized
to be capable of supporting all recording for the Cisco Unified CCX cluster. For example, under normal
operating conditions, a large call center may be set up to handle 16 recording sessions on each Recording
component, for a total of 32 simultaneous call recordings. If either server with a Recording component
fails, the other server processes all call recordings. In this failure scenario, make sure that the total
number of call recordings does not exceed the server capacity that is shown in the Cisco Unified
Communications Sizing Tool.
function properly during a period when one of the servers fails, the two Recording servers must be sized
to be capable of supporting all recording for the Cisco Unified CCX cluster. For example, under normal
operating conditions, a large call center may be set up to handle 16 recording sessions on each Recording
component, for a total of 32 simultaneous call recordings. If either server with a Recording component
fails, the other server processes all call recordings. In this failure scenario, make sure that the total
number of call recordings does not exceed the server capacity that is shown in the Cisco Unified
Communications Sizing Tool.
Recording requires a Monitoring component. When SPAN port monitoring is configured for silent
monitoring, the SPAN port monitoring server forwards the RTP stream to the Recording component. If
that SPAN port monitoring server fails, recording is not possible. When desktop monitoring is
configured, the Monitoring component is still required in order for CAD to retrieve the agent phone’s
monitoring, the SPAN port monitoring server forwards the RTP stream to the Recording component. If
that SPAN port monitoring server fails, recording is not possible. When desktop monitoring is
configured, the Monitoring component is still required in order for CAD to retrieve the agent phone’s