Providing Open Architecture High Availability Solutions

Providing Open Architecture High Availability Solutions
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10.2 Configuring and Maintaining State-Aware Model of the Total
System
Availability management requires a system-wide model that can represent all managed components
in the system, changing information and the intricacies of each component’s dependencies and
interdependencies. The management software needs this information to make quick and
appropriate reconfigurations when necessary.
Components that rely upon another component or set of components in order to work can be
represented not only as a parent/child dependency relationship, but more importantly as a dual-
connected directed graph (digraph) in which each component is linked to every other component
upon which it depends, and each component is linked to every component that depends on it. Such
dependencies can span a complex array of branching interdependencies. An example of a system
and the directed graph which represent it are shown in Figure 16 and Figure 17. Availability
management must understand role relationships and the consequences of component failure and
role reassignments. Both the dependent and the depended-upon relations need to be monitored in a
system model and dynamically reconfigured as needed.
Figure 16. Example of a Managed System
A8681-01
Power Supplies
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