Explanation:
Archive logs can be written to multiple destinations. Oracle allows you to multiplex your archived redo logs by specifying a few new init.ora parameters. The first is LOG_ARCHIVE_DUPLEX_DEST, and it's used to identify the second location where Oracle will store copies of archived redo logs. The second new init.ora parameter is the LOG_ARCHIVE_MIN_SUCCEED_DEST parameter. This is set a number indicating how many archive log copies Oracle should maintain.
Incorrect Answers:
1: Archiving works constantly, not only during a checkpoint.
3: Backups are required always, with enabled archiving also.
4: Archiving works only with redo log files, not with data files.
5: Archiving cannot be enabled trough recovery manager commands.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 583-585
Chapter 12: Overview of Backup and Recovery

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