asm 磁盘组，更改磁盘大小

参考：Doc ID 470209.1

#The present document shows an example to resize the ASM disks on 10.2 version

1,建议备份数据库

2，关闭数据库

3，dismount磁盘组

SQL> alter diskgroup <diskgroup> dismount;

4，硬件层面disk/LUN  resize

5,mount磁盘组

SQL> alter diskgroup <diskgroup> mount;

6，重新resize磁盘大小

命令参考：

Resizing Disks in Disk Groups
The RESIZE clause of ALTER DISKGROUP enables you to resize disks in a disk group.

When resizing disks in a disk group, all the disks must be of equal size.

If you do not specify a new size in the SIZE clause, then Oracle ASM uses the size of the disks as returned by the operating system. The new size is written to the Oracle ASM disk header and if the size is increasing, then the new space is immediately available for allocation. If the size is decreasing, rebalancing must relocate file extents beyond the new size limit to available space below the limit. If the rebalance operation can successfully relocate all extents, then the new size is made permanent, otherwise the rebalance fails.

The following example resizes all of the disks in the disk group data1. If the new size is greater than the capacity of a disk, then the statement fails.

Example 4-6 Resizing disks in disk groups

ALTER DISKGROUP data1 RESIZE ALL SIZE 100G;