Cisco Cisco Workload Automation 6.3 Installation Guide

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Installing Fault Tolerance
Overview of Fault Tolerance
Fault Tolerance Configuration
Fault tolerance has two configuration modes: auto mode and fixed mode.
Auto mode
Auto mode is the default way of configuring fault tolerance. If the Primary Master fails and the Backup Master assumes 
control, then the Backup Master assumes the active role. When the Primary Master that failed comes back online, it 
remains in standby mode. This type of fault tolerance does not care if the original Primary Master is actively controlling 
the production or if the configured Backup Master is in control. Regardless of the original configuration, each Master is 
interchangeable and can operate in either an active or standby mode. See also, 
Fixed Mode
In fixed mode, if the Primary Master fails, the Backup Master assumes control just as with auto mode. However, in fixed 
mode, when the Backup Master assumes control, it continues the production schedule until control is manually switched 
back to the Primary Master. During the time the Backup Master controls the production schedule, fault tolerance is 
disabled. Fault tolerance is enabled again when the Primary Master resumes control. In the backup mode, fault tolerance 
is disabled because the Backup Master does not have a backup.
 
During a failover, the green light beside the Fault Monitor name (located in the first column of the Connections pane) turns 
red. This light indicates that fault tolerance is not operating. 
The status lights warn users that without Master redundancy, the network is vulnerable to failure. Returning the Primary 
Master to service and restoring your system to a normal fault tolerant status should be the highest priority. Use the switch 
back procedure to return the Primary Master to service. See 
.
In the Unix installation procedure after providing a directory location for the installation files, a screen asks if you wish to 
install a Primary Master or Backup Master. You should install the Primary Master first. Complete the Primary Master 
installation and then repeat the Master installation on a different machine, selecting the Backup Master option for the 
second installation. For more information on installing the primary and Backup Masters for Unix, refer to 
Fault Tolerance Operational Modes
Whenever the Primary Master is running while the Backup Master remains available to assume control, the system is in 
normal standby mode. If the Primary Master is unable to run, control of the production schedule passes to the Backup 
Master ensuring uninterrupted production. Whenever the Backup Master assumes control from the Primary Master, the 
system is in backup mode.