Explanation:
RMAN can automatically back up the control file and server parameter file whenever the database structure metadata in the control file changes and whenever a backup or copy record is added. If CONFIGURE CONTROL FILE AUTO BACKUP is ON (by default it is OFF), then RMAN automatically backs up the control file and the current server parameter file (if used) in the following circumstances:
• After every BACKUP or COPY command issued at the RMAN prompt.
• Whenever a BACKUP or COPY command within a RUN block is followed by a command that is neither BACKUP nor COPY.
• At the end of every RUN block if the last command in the block was either BACKUP or COPY.
• After database structural changes such as adding a new table space, altering the state of a table space or data file (for example, bringing it online), adding a new online redo log, renaming a file, adding a new redo thread, and so forth. This type of auto backup, unlike auto backups that occur in the preceding circumstances, is only on disk. You can run CONFIGURE CONTROL FILE AUTO BACKUP FOR DEVICE TYPE DISK to set a non default disk location.
Note that the auto backup never causes the associated structural change to fail. For example, if you add a data file, and if the resulting auto backup fails, then the data file addition is still successful. Incorrect Answer:
1: RMAN does not automatically perform a control file auto backup at the end of every RUN block.
2: The SET CONTROL FILE AUTO BACKUP FORMAT command does not cause automatic control file backup.
6: RMAN does not automatically perform a control file auto backup in this situation.
Reference:
OCP Oracle 9i Database: Fundamentals II Exam Guide, Rama Velpuri, p. 324-325
Chapter 13: RMAN Complete Recovery

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