This illustration shows the Maximum Availability Architecture (MAA). The MAA architecture consists of identical primary and secondary sites.
The primary site contains storage on an Oracle RAC database, two Oracle RAC database instances, and an Oracle Application Server. The secondary site is exactly the same except it is connected to the WAN traffic manager by a dotted to indicate that the secondary site is not actively handling application requests at this time.
A dedicated network connects the primary site and the standby site. Data Guard transmits redo data from the primary site to the secondary site. A WAN traffic manager handles communication between the application servers on the primary and secondary sites. Clients send requests through the WAN traffic manager.
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