Cisco Cisco IPCC Web Option Leaflet
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Cisco Unified Contact Center Enterprise 7.5 SRND
Chapter 3 Design Considerations for High Availability
Peripheral Gateway Design Considerations
To simplify the illustration in
, the ICM Server or ICM Central Controller is represented as
a single server, but it is actually a set of servers sized according to the Unified CCE agent count and call
volume. The ICM Central Controllers include the following redundant/duplex servers:
volume. The ICM Central Controllers include the following redundant/duplex servers:
•
Call Router — The "brain" of the ICM complex that provides intelligent call routing instructions
based on real-time conditions it maintains in memory across both the A-Side and B-Side Call Router
processes.
based on real-time conditions it maintains in memory across both the A-Side and B-Side Call Router
processes.
•
Logger/Database Server — The repository for all configuration and scripting information as well as
historical data collected by the system. The Loggers are "paired" with their Call Routers such that
Call Router Side A will read and write data only to the Logger A, and the Call Router B will read
and write only to the Logger B. Because both sides of the Call Router processes are synchronized,
the data written to both Loggers is identical.
historical data collected by the system. The Loggers are "paired" with their Call Routers such that
Call Router Side A will read and write data only to the Logger A, and the Call Router B will read
and write only to the Logger B. Because both sides of the Call Router processes are synchronized,
the data written to both Loggers is identical.
In specific deployment models, these two components can be installed on the same physical server,
which is referred to as a Rogger, or combined Router/Logger. Refer to the chapter on
which is referred to as a Rogger, or combined Router/Logger. Refer to the chapter on
, for more details on these specific configurations.
Unified CM JTAPI and Peripheral Gateway Failure Detection
There is a heartbeat mechanism that is used to detect failures between the Unified CM JTAPI link and
the Peripheral Gateway. However, unlike the ICM heartbeat methods that use TCP keep-alive messages
on the open socket ports, this method uses a specific heartbeat message in the JTAPI messaging protocol
between the systems. By default, the heartbeat messages are sent every 30 seconds, and the
communications path is reset by the Unified CM or Peripheral Gateway after missing two consecutive
heartbeat messages.
the Peripheral Gateway. However, unlike the ICM heartbeat methods that use TCP keep-alive messages
on the open socket ports, this method uses a specific heartbeat message in the JTAPI messaging protocol
between the systems. By default, the heartbeat messages are sent every 30 seconds, and the
communications path is reset by the Unified CM or Peripheral Gateway after missing two consecutive
heartbeat messages.
This failure detection can be enhanced by using the following procedure to change the heartbeat interval
on the JTAPI Gateway client that runs on the Peripheral Gateway:
on the JTAPI Gateway client that runs on the Peripheral Gateway:
Step 1
From the Start Menu of the Peripheral Gateway, Select Programs -> Cisco JTAPI -> JTAPI
Preferences.
Preferences.
Step 2
Set the Advanced -> Server Heartbeat Interval (sec) field to 5 seconds.
Cisco recommends that you do not set this value lower than five seconds because it might impact system
performance and trigger an inappropriate failover. This setting determines how often the heartbeats are
generated. If it is set to five seconds, the system will fail-over this connection within ten seconds of a
loss of network connection because it must detect two consecutive missed heartbeats. The default of
30 seconds takes up to one minute (60 seconds) to take action on a network connection failure.
performance and trigger an inappropriate failover. This setting determines how often the heartbeats are
generated. If it is set to five seconds, the system will fail-over this connection within ten seconds of a
loss of network connection because it must detect two consecutive missed heartbeats. The default of
30 seconds takes up to one minute (60 seconds) to take action on a network connection failure.
Because this JTAPI connection between the Peripheral Gateway and Unified CM is supported only
locally on the same LAN segment, there should not be an issue with latency for this heartbeat value.
However, if there are any additional network hops, firewalls, or other devices that cause delay between
these two components, then the heartbeat interval value should be set accordingly to account for this
possible condition.
locally on the same LAN segment, there should not be an issue with latency for this heartbeat value.
However, if there are any additional network hops, firewalls, or other devices that cause delay between
these two components, then the heartbeat interval value should be set accordingly to account for this
possible condition.