没想到这么简单的操作，由于不熟悉还碰到了两个小问题。

[oracle@dbserver1 ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.2.0 Production on Tue Aug 9 10:08:06

2011

Copyright (c) 1982, 2010, Oracle.All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production

With the Partitioning, Automatic Storage Management, OLAP, Data Mining

and Real Application Testing options

SQL> set pages 100 lines 120

SQL> select group_number, name, state, type, total_mb, free_mb

2from v$asm_diskgroup;

GROUP_NUMBER NAMESTATETYPETOTAL_MBFREE_MB

------------ ------------------------------ ----------- ------ ----------

----------

1 DATA_AU1MCONNECTEDEXTERN19531247430

2 DATA_AU2MCONNECTEDEXTERN19531247384

3 DATA_AU4MCONNECTEDEXTERN19531247304

4 DATACONNECTEDEXTERN39062483898966

SQL> col path format a30

SQL> col name format a30

SQL> select disk_number, path, name, total_mb, free_mb

2from v$asm_disk

3where group_number = 4;

DISK_NUMBER PATHNAMETOTAL_MBFREE_MB

----------- ------------------------- ------------------------- ----------

----------

1 /dev/asm-disk5DATA_000119531241949486

0 /dev/asm-disk4DATA_000019531241949480

SQL> alter diskgroup data drop disk '/dev/asm-disk5';

alter diskgroup data drop disk '/dev/asm-disk5'

*

ERROR at line 1:

ORA-15000: command disallowed by current instance type

SQL> exit

Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 -

64bit Production

With the Partitioning, Automatic Storage Management, OLAP, Data Mining

and Real Application Testing options

由于当前连接的是数据库，显然不能对ASM实例中的磁盘组进行操作，下面连接ASM实例：

[oracle@dbserver1 ~]$ su - grid

Password:

[grid@dbserver1 ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.2.0

Production on Tue Aug 9 10:12:39 2011

Copyright (c) 1982, 2010, Oracle.

All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production

With the Automatic Storage Management option

SQL> set pages 100 lines 120

SQL> select instance_number, instance_name from v$instance;

INSTANCE_NUMBER INSTANCE_NAME

--------------- ----------------

1 +ASM

SQL> alter diskgroup data drop

disk '/dev/asm-disk5';

alter diskgroup data drop disk '/dev/asm-disk5'

*

ERROR at line 1:

ORA-15032: not all alterations performed

ORA-15260: permission denied on ASM disk group

SQL> alter diskgroup data drop disk data_0001;

alter diskgroup data drop disk data_0001

*

ERROR at line 1:

ORA-15032: not all alterations performed

ORA-15260: permission denied on ASM disk group

开始看到这个错误还确实疑惑了一下，怎么可能没有权限。有在操作系统上检查了磁盘的权限，也没有任何问题。

检查Oracle文档的错误信息后发现，由于习惯了适用sysdba来处理，忽略了当前是11g的ASM，应该用sysasm来登录：

SQL> conn / as sysasm

Connected.

SQL> alter diskgroup data drop disk data_0001;

Diskgroup altered.

SQL> select disk_number, state, name, total_mb, free_mb from

v$asm_disk where group_number = 4;

DISK_NUMBER STATE NAMETOTAL_MBFREE_MB

----------- -------- ------------------------------ ---------- ----------

1 DROPPING DATA_000119531241950842

0 NORMALDATA_000019531241948124

SQL> select disk_number, state, name, total_mb, free_mb from

v$asm_disk where group_number = 4;

DISK_NUMBER STATENAMETOTAL_MBFREE_MB

----------- -------- ------------------------------ ---------- ----------

1 DROPPING DATA_000119531241951434

0 NORMALDATA_000019531241947532

SQL> select disk_number, state, name, total_mb, free_mb from

v$asm_disk where group_number = 4;

DISK_NUMBER STATENAMETOTAL_MBFREE_MB

----------- -------- ------------------------------ ---------- ----------

1 DROPPING DATA_000119531241952556

0 NORMALDATA_000019531241946410

SQL> select disk_number, state, name, total_mb, free_mb from

v$asm_disk where group_number = 4;

DISK_NUMBER STATENAMETOTAL_MBFREE_MB

----------- -------- ------------------------------ ---------- ----------

1 DROPPING DATA_000119531241953096

0 NORMALDATA_000019531241945870

SQL> select disk_number, state, name, total_mb, free_mb from

v$asm_disk where group_number = 4;

DISK_NUMBER STATENAMETOTAL_MBFREE_MB

----------- -------- ------------------------------ ---------- ----------

0 NORMALDATA_000019531241945854

SQL> select group_number, disk_number, path, name, state,

total_mb, free_mb

2from v$asm_disk

3where path = '/dev/asm-disk5';

GROUP_NUMBER DISK_NUMBER PATHNAMESTATETOTAL_MBFREE_MB

------------ ----------- --------------- ---------- -------- ----------

----------

01 /dev/asm-disk5NORMAL00

可以看到，虽然删除操作执行完成，但是磁盘并没有真正被删掉，ASM在后台尝试将磁盘上的数据挪到其他可用磁盘中，这时磁盘的状态为DROPPING。

当后台数据同步的操作完成，磁盘的组信息被清除，磁盘恢复STATE状态。这时这个磁盘就从ASM中被彻底删除。