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Connecting to a Target Database in an Oracle Real Application Cluster
RMAN can only connect to one instance in an Oracle Real Application Clusters database at a time. Assume that trgt1, trgt2, and trgt3 are net service names for three instances in an Oracle Real Application Clusters configuration. In this case, you can connect to the target database using only one of these net service names. For example, you can connect as follows:
% rman TARGET SYS/oracle@trgt2 CATALOG rman/cat@catdb
Each net service name must specify one and only one instance. You cannot specify a net service name that uses Oracle Net features to distribute connections to more than one instance.
Note that the fact that RMAN connects to only one instance for its initial target connection does not preclude running a backup using all three instances. For example, you can configure automatic channels to connect to each cluster instance as follows:
CONFIGURE DEFAULT DEVICE TYPE TO sbt;
CONFIGURE DEVICE TYPE sbt PARALLELISM 3;
CONFIGURE CHANNEL 1 DEVICE TYPE sbt CONNECT = 'SYS/oracle@trgt1';
CONFIGURE CHANNEL 2 DEVICE TYPE sbt CONNECT = 'SYS/oracle@trgt2';
CONFIGURE CHANNEL 3 DEVICE TYPE sbt CONNECT = 'SYS/oracle@trgt3';
