Johnson Controls tyco iSTAR Ultra, Installation And Configuration Manual

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Maintaining Cluster Communication
3–10 iSTAR Ultra Installation and Configuration Guide
Maintaining Cluster Communication
Maintaining cluster communications involves establishing and maintaining connections via
the primary communication path or (optional) secondary communication path. If the primary
connection is lost, the secondary communication path is used to re-establish cluster
communications.
Single Master Configurations
If a configuration with a single master loses its connection with the host, as shown in
Figure 3-7 on page 3-10 :

Cluster members continue to communicate with the master.

The master continues to pass cluster members’ messages to the host.

The master uses the secondary path to communicate with the host.
Example:
If the secondary path is an alternate network connection between the master and host, the
master uses the alternate network to communicate with the host.
Figure 3-7: Communication Failure with Single Master Configuration
Host
Ultra Master
Network Failure
Member
Member