Explanation:
There are two ways that online redo logs will be archived: either manually, with the ALTER SYSTEM ARCHIVE LOG statement, or automatically by ARCH. Manual archiving is not recommended because of a DBA must issue an SQL command to archive manually the online redo log files.
Incorrect Answers:
1: Additional disk resources are not required for manual archiving.
2: There is no additional background processes are required for manual archiving.
4: A DBA can issue just an SQL command to archive redo log files manually, an operation systems script is not required for this purpose.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 576-577
Chapter 12: Overview of Backup and Recovery

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