（649）Examine the CREATE DISKGROUP command used to create a disk group:

SQL>CREATE DISKGROUP misc EXTERNAL REDUNDANCY DISK 'ORCL:FRA3' NAME misc1, 'ORCL:FRA4' NAME misc2;

In which situation would you use this method of disk group creation?

A. When two-way disk mirroring is required for the allocation units

B. When three-way disk mirroring is required for the allocation units

C. When using hardware mirroring or RAID

D. When disk mirroring is required for the Automatic Storage Management（ASM）disk

答案：（C）

解析：

（创建ASM磁盘组时选择外部冗余的唯一原因是在阵列这一层已经实现了包含，比如各种raid技术）

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Oracle 11G OCP 1Z0-053 649