AFFIRM—specifies that all disk I/O to archived redo log files and standby redo log files is performed synchronously and completes successfully before the log writer process continues.
NOAFFIRM—specifies that all disk I/O to archived redo log files and standby redo log files is performed asynchronously; the log writer process on the primary database does not wait until the disk I/O completes before continuing.
Specifies when redo transport services transmit redo data to a destination, based on the following factors:
Whether the database is currently running in the primary or the standby role
Whether online redo log files, standby redo log files, or both are currently being archived on the database at this destination
To configure these factors for each LOG_ARCHIVE_DEST_n destination, you specify this attribute with a pair of keywords: VALID_FOR=(redo_log_type,database_role):
The redo_log_type keyword identifies the destination as valid for archiving one of the following:
ONLINE_LOGFILE—This destination is valid only when archiving online redo log files.
STANDBY_LOGFILE—This destination is valid only when archiving standby redo log files.
ALL_LOGFILES— This destination is valid when archiving either online redo log files or standby redo log files.
The database_role keyword identifies the role in which this destination is valid for archiving:
PRIMARY_ROLE—This destination is valid only when the database is running in the primary role.
STANDBY_ROLE—This destination is valid only when the database is running in the standby role.
ALL_ROLES—This destination is valid when the database is running in either the primary or the standby role
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