OCP-1Z0-053-V12.02-21题

21.You are managing an Oracle Database 11g instance. You want to create a duplicate database for

testing purpose.

What are the prerequisites for performing the active database duplication? (Choose all that apply.)

A. The source database backup must be copied over the net for test database.

B. The source database must be run in ARCHIVELOG mode if the database is open.

C. The source database must be shut down cleanly if the database is in mounted state.

D. A net service name should be set up and a listener configured with the target as well as the source

database.

Answer: BCD

答案解析：

参考：http://blog.csdn.net/rlhua/article/details/13509067

官方参考：http://docs.oracle.com/cd/E11882_01/backup.112/e10643/rcmsynta020.htm#RCMRF90152

通过使用Oracle Enterprise Manager 或RMAN DUPLICATE命令的FROM ACTIVE DATABASE子句，可以指示源数据库直接将映像副本和归档日志副本复制到辅助实例。

此操作不需要使用备份。RMAN 作为TARGET连接到源数据库实例并作为AUXILIARY连接到辅助实例。

通过实例间的网络连接将数据库文件从源数据库复制到目标数据库或辅助实例。RMAN 随后使用“内存脚本”（仅包含在内存中）完成恢复并打开数据库。

Active duplication：RMAN duplicates the files directly from either an open or mounted database.

A,从活动数据库复制，不需要拷贝备份。错误。

B,源数据库必须是归档模式，正确。

C，如果数据库是mount状态，那么源数据库一定是shut down cleanly。正确。

D，需要建立网络服务名和配置监听。正确。

Prerequisites Specific to Active Database Duplication

When you execute DUPLICATE with FROM ACTIVE DATABASE, at least one normal target channel and at least one AUXILIARY channel are required.

When you connect RMAN to the source database as TARGET, you must specify a password, even if RMAN uses operating system authentication. The source database must be mounted or open. If the source database is open, then archiving must be enabled. If the source database is not open, then it must have been shut down consistently.

When you connect RMAN to the auxiliary instance, you must provide a net service name. This requirement applies even if the auxiliary instance is on the local host.

The source database and auxiliary instances must use the same SYSDBA password, which means that both instances must have password files. You can create the password file with a single password so you can start the auxiliary instance and enable the source database to connect to it.

The DUPLICATE behavior for password files varies depending on whether your duplicate database acts as a standby database. If you create a duplicate database that is not a standby database, then RMAN does not copy the password file by default. You can specify the PASSWORD FILE option to indicate that RMAN should overwrite the existing password file on the auxiliary instance. If you create a standby database, then RMAN copies the password file to the standby host by default, overwriting the existing password file. In this case, the PASSWORD FILE clause is not necessary.

You cannot use the UNTIL clause when performing active database duplication. RMAN chooses a time based on when the online data files have been completely copied, so that the data files can be recovered to a consistent point in time.