• LOG_ARCHIVE_DEST_n Parameter Attributes
  Example 15-1 Automatically Failing Over to an Alternate Destination LOG_ARCHIVE_DEST_1='LOCATION=/disk1 MANDATORY ALTERNATE=LOG_ARCHIVE_DEST_2' LOG_ARCHIVE_DEST_STATE_1=ENABLE LOG_ARCHIVE_DEST_2='LOCATION=/disk2 MANDATORY' LOG_ARCHIVE_DEST_STATE_2=ALTERNATE Notice in the example that a destination can also be in the ALTERNATE state, as specified with the LOG_ARCHIVE_DEST_STATE_n initialization parameter. The ALTERNATE state defers redo transport services from transmitting redo data to this destination until such time as another destination failure automatically enables this destination.
  in Oracle > Oracle Tips with alternate automatically defers destination enable example failing initialization location log_archive_dest_1 log_archive_dest_2 log_archive_dest_state_1 log_archive_dest_state_2 mandatory redo

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