Arcserve RHA monitors all critical events, including global server failure and all database service failures. You may configure Arcserve RHA to automatically reverse server roles, called failover, or manually switch server roles, called switchover, when a critical event is detected. This means the Replica server becomes active while the Master server stands by.
Note: Automatic failover and manual switchover settings are configured during High Availability scenario creation. You may also configure these settings from the Arcserve RHA Manager Properties tab and expand the Switchover Settings properties group.
When the Master server becomes unavailable, its activities are failed over automatically to a remote site (Replica). The failover, which is transparent to the user, includes immediate startup of a synchronized standby database. All users are redirected to it in minimum time. All this is done without any need to reconfigure either clients or the network.
Redirection can be based on the following methods:
Note: You can also apply user-defined scripts that add or replace the built-in redirection methods. Identify Network Traffic Direction scripts are required to fully support custom, or customized, redirection methods. Custom scripts or batch files are used to identify the active server. This script determines if the forward or backward scenario will run when the scenario is started. The script runs on both the Master and Replica: the one that returns zero is active. If both return zero, a conflict is reported.
Redirection method selection is based on the requirements of the application being protected; certain methods may not apply to a particular scenario. For more information, see the application-specific Operation Guide.
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