Each time Mirror Replication Agent performs log truncation (either scheduled or manual) it issues the alter system command with the archive log sequence keywords. The command uses the log sequence number of the redo log file whose contents have been processed by the Mirror Replication Agent and are ready to be archived.
The alter system command syntax in
Oracle allows redo log files to be archived in addition to the single
log sequence specified in the command. To avoid the possibility
of unintentional archiving, Mirror Replication Agent only issues this command
when it is processing the redo log file whose status is CURRENT.
You can specify the automatic truncation option you want (including none) by using the ra_config command to set the value of the truncation_type configuration parameter.
If you want to truncate the transaction log automatically based on a time interval, use the ra_config command to set the value of the truncation_interval configuration parameter.
At any time, you can truncate the Mirror Replication Agent transaction log manually by invoking the pdb_truncate_xlog command at the Mirror Replication Agent administration port.
Mirror Replication Agent creates objects in the Oracle primary database to assist with replication tasks.
