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
Cisco Unified CCX Fault Tolerance
The Cisco Unified CCX solution offers a number of capabilities to provide fault tolerance. To begin
with, a Cisco Unified CCX deployment utilizes a Cisco Unified Communications network composed of
Cisco data switches and routers, which provide for a highly available data network with many options
for redundancy. Cisco campus and network design guides discuss best practices for designing highly
available networks with Cisco switches and routers.
with, a Cisco Unified CCX deployment utilizes a Cisco Unified Communications network composed of
Cisco data switches and routers, which provide for a highly available data network with many options
for redundancy. Cisco campus and network design guides discuss best practices for designing highly
available networks with Cisco switches and routers.
A Cisco Unified CM deployment utilizes a cluster approach with up to eight call processing servers per
Cisco Unified CM cluster. Cisco Unified CM groups devices (voice gateways, IP Phones, and CTI Ports)
into device pools and allows for device pools to have a primary, secondary, and tertiary Cisco Unified
CM server. When a device pool’s primary Cisco Unified CM server fails, the devices within that device
pool automatically fail over to the secondary or tertiary Cisco Unified CM server. Unified CCX CTI
Ports are grouped together into CTI call control groups (often called a CTI port group). Each CTI port
group is configured as part of a device pool. Cisco Unified CM also supports voice gateways deployed
at many locations with trunks from different service providers.
Cisco Unified CM cluster. Cisco Unified CM groups devices (voice gateways, IP Phones, and CTI Ports)
into device pools and allows for device pools to have a primary, secondary, and tertiary Cisco Unified
CM server. When a device pool’s primary Cisco Unified CM server fails, the devices within that device
pool automatically fail over to the secondary or tertiary Cisco Unified CM server. Unified CCX CTI
Ports are grouped together into CTI call control groups (often called a CTI port group). Each CTI port
group is configured as part of a device pool. Cisco Unified CM also supports voice gateways deployed
at many locations with trunks from different service providers.
Cisco Unified CM has a subsystem called the CTI Manager that abstracts the device management from
the JTAPI communications to an application server (like Cisco Unified CCX). This implementation
allows an application to not be concerned with what specific server a device (voice gateway, agent
phone, or CTI port) is currently registered. Cisco Unified CCX has the ability to communicate with up
to two CTI Managers within a Cisco Unified CM cluster, but only actively communicates with one at a
time. If the active CTI Manager subsystem or the Cisco Unified CM node running the active CTI
Manager fails, Cisco Unified CCX closes the sockets for all CTI ports and immediately begins JTAPI
communications with the backup CTI Manager. Calls being handled by agents survive, but if their
phones are registered with the failed Cisco Unified CM, they will not be able to perform any subsequent
call control. Upon completion of existing calls, agent phones will automatically re-register to the
secondary Cisco Unified CM server. For agents who were not off hook, their phones will re-register to
the secondary Cisco Unified CM immediately.
the JTAPI communications to an application server (like Cisco Unified CCX). This implementation
allows an application to not be concerned with what specific server a device (voice gateway, agent
phone, or CTI port) is currently registered. Cisco Unified CCX has the ability to communicate with up
to two CTI Managers within a Cisco Unified CM cluster, but only actively communicates with one at a
time. If the active CTI Manager subsystem or the Cisco Unified CM node running the active CTI
Manager fails, Cisco Unified CCX closes the sockets for all CTI ports and immediately begins JTAPI
communications with the backup CTI Manager. Calls being handled by agents survive, but if their
phones are registered with the failed Cisco Unified CM, they will not be able to perform any subsequent
call control. Upon completion of existing calls, agent phones will automatically re-register to the
secondary Cisco Unified CM server. For agents who were not off hook, their phones will re-register to
the secondary Cisco Unified CM immediately.
In addition to being able to fail over to another Cisco Unified CM node within the cluster, Cisco Unified
CCX itself provides a clustering mechanism. In a high availability deployment, up to two servers can be
deployed, each server configured with the Cisco Unified CCX Engine and Database components with
the optional, Monitoring and Recording components.
CCX itself provides a clustering mechanism. In a high availability deployment, up to two servers can be
deployed, each server configured with the Cisco Unified CCX Engine and Database components with
the optional, Monitoring and Recording components.
The four components all provide some level of redundancy and fault tolerance, but each functions a bit
differently.
differently.
Cisco Unified CCX Engine Redundancy
When deploying with high availability, two Cisco Unified CCX Engine components must be deployed
on separate servers. If one server initiates the engine mastership election first, it becomes master. The
other server becomes standby. If both servers are started approximately at the same time, it is not
specified which server becomes master. It the Cisco Unified CCX Engine component server fails over,
the standby server becomes the master server and remains as the master server until another failure
occurs. Any active calls being processed by applications on CTI Ports will be released upon failure of
the master Cisco Unified CCX Engine server.
on separate servers. If one server initiates the engine mastership election first, it becomes master. The
other server becomes standby. If both servers are started approximately at the same time, it is not
specified which server becomes master. It the Cisco Unified CCX Engine component server fails over,
the standby server becomes the master server and remains as the master server until another failure
occurs. Any active calls being processed by applications on CTI Ports will be released upon failure of
the master Cisco Unified CCX Engine server.
All ACD, IVR, and desktop services will failover within 5 seconds. Any incoming call arriving at Cisco
Unified CM destined for Cisco Unified CCX route points can be accepted by the Cisco Unified CCX
engine and all Cisco Unified CCX call treatment and ACD routing services are operational.
Automatically logging on large numbers of agents may take up to 1 minute. For a given agent, the ACD
is not able to route calls to agents until the automatic login process completes and the agent manually
sets the state to Ready. Agents on Cisco Unified CCX routed calls will see those calls survive and CAD
Unified CM destined for Cisco Unified CCX route points can be accepted by the Cisco Unified CCX
engine and all Cisco Unified CCX call treatment and ACD routing services are operational.
Automatically logging on large numbers of agents may take up to 1 minute. For a given agent, the ACD
is not able to route calls to agents until the automatic login process completes and the agent manually
sets the state to Ready. Agents on Cisco Unified CCX routed calls will see those calls survive and CAD