Oracle 12.2报错ORA-15032、ORA-15410或ORA-15411解决

现象：在Oracle 12.2.0.1 RAC环境，在其ASM实例中，如果添加不同大小或者不同数量的LUN到failgroup中，会报错：

ORA-15032: not all alterations performed
ORA-15410: Disks in disk group OCRVT do not have equal size.
或者
ORA-15032: not all alterations performed
ORA-15411: Failure groups in disk group OCRVT have different number of disks.

解决方案：

动态修改这两个隐藏参数可以解决：

alter system set "_asm_disable_failgroup_size_checking"=true;
alter system set "_asm_disable_dangerous_failgroup_checking"=true;

下面举一个实际的例子：

比如新加的LUN：mpathi，mpathj，mpathk都是200M大小，以前的ASM磁盘组OCRVT由3个LUN：mpatha，mpathb，mpathc都是1G大小组成；现在想把新的LUN加到OCRVT磁盘组中：

SQL>  select name, failgroup, path, mode_status, voting_file from v$asm_disk;
NAME                                FAILGROUP                      PATH                                          MODE_ST V
----------------------------------- ------------------------------ --------------------------------------------- ------- -
                                                                   /dev/mapper/mpathj                            ONLINE  N
                                                                   /dev/mapper/mpathi                            ONLINE  N
                                                                   /public/nfsdisk                               ONLINE  N
                                                                   /dev/mapper/mpathk                            ONLINE  N
DATA_0001                           DATA_0001                      /dev/mapper/mpathf                            ONLINE  N
FRA_0000                            FRA_0000                       /dev/mapper/mpathh                            ONLINE  N
DATA_0002                           DATA_0002                      /dev/mapper/mpathg                            ONLINE  N
DATA_0000                           DATA_0000                      /dev/mapper/mpathe                            ONLINE  N
MGMT_0000                           MGMT_0000                      /dev/mapper/mpathd                            ONLINE  N
OCRVT_0000                          OCRVT_0000                     /dev/mapper/mpathc                            ONLINE  Y
OCRVT_0002                          OCRVT_0002                     /dev/mapper/mpathb                            ONLINE  Y
OCRVT_0001                          OCRVT_0001                     /dev/mapper/mpatha                            ONLINE  Y
12 rows selected.

直接尝试添加新的LUN到ASM磁盘组OCRVT中，会报错。依次尝试设置相关的隐藏参数，可以成功添加：

SQL> alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi';
alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi'
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15410: Disks in disk group OCRVT do not have equal size.
SQL> alter system set "_asm_disable_dangerous_failgroup_checking"=true;
System altered.
SQL> alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi';
alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi'
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15411: Failure groups in disk group OCRVT have different number of disks.
SQL> alter system set "_asm_disable_failgroup_size_checking"=true;
System altered.
SQL>  alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi';
Diskgroup altered.

总结：

asm中与failgroup相关的隐藏参数:

_asm_disable_dangerous_failgroup_checking FALSE

_asm_disable_failgroup_count_checking FALSE

_asm_disable_failgroup_size_checking FALSE

SQL> r
  1  SELECT   i.ksppinm name,
  2     i.ksppdesc description,
  3     CV.ksppstvl VALUE
  4  FROM   sys.x$ksppi i, sys.x$ksppcv CV
  5     WHERE   i.inst_id = USERENV ('Instance')
  6     AND CV.inst_id = USERENV ('Instance')
  7     AND i.indx = CV.indx
  8     AND i.ksppinm LIKE '%&param%'
  9* ORDER BY   REPLACE (i.ksppinm, '_', '')
Enter value for param: failgroup
old   8:    AND i.ksppinm LIKE '%&param%'
new   8:    AND i.ksppinm LIKE '%failgroup%'
NAME                                DESCRIPTION                                                        VALUE
----------------------------------- ------------------------------------------------------------------ ------------------------------
_asm_disable_dangerous_failgroup_ch Disable checking for dubious failgroup configurations              FALSE
ecking
_asm_disable_failgroup_count_checki Disable checking for failure group count                           FALSE
ng
_asm_disable_failgroup_size_checkin Disable checking for failure group size                            FALSE
g
--这类参数实测可以动态修改：
alter system set "_asm_disable_failgroup_size_checking"=true;
alter system set "_asm_disable_dangerous_failgroup_checking"=true;
--alter system set "_asm_disable_failgroup_count_checking"=true; 这个参数我没有测出来实际作用，实测只需要上面两个参数设置为true就同样可以允许failgroup的数量不一致。
SQL> show parameter _asm
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
_asm_disable_dangerous_failgroup_che boolean     TRUE
cking
_asm_disable_failgroup_size_checking boolean     TRUE
--test
SQL> select name, failgroup, path, mode_status, voting_file from v$asm_disk;
NAME                                FAILGROUP                      PATH                                          MODE_ST V
----------------------------------- ------------------------------ --------------------------------------------- ------- -
                                                                   /public/nfsdisk                               ONLINE  N
OCRVT_0005                          OCRVT_0002                     /dev/mapper/mpathk                            ONLINE  N
OCRVT_0004                          OCRVT_0001                     /dev/mapper/mpathj                            ONLINE  N
DATA_0001                           DATA_0001                      /dev/mapper/mpathf                            ONLINE  N
OCRVT_0003                          OCRVT_0000                     /dev/mapper/mpathi                            ONLINE  N
FRA_0000                            FRA_0000                       /dev/mapper/mpathh                            ONLINE  N
DATA_0002                           DATA_0002                      /dev/mapper/mpathg                            ONLINE  N
DATA_0000                           DATA_0000                      /dev/mapper/mpathe                            ONLINE  N
MGMT_0000                           MGMT_0000                      /dev/mapper/mpathd                            ONLINE  N
OCRVT_0000                          OCRVT_0000                     /dev/mapper/mpathc                            ONLINE  Y
OCRVT_0002                          OCRVT_0002                     /dev/mapper/mpathb                            ONLINE  Y
OCRVT_0001                          OCRVT_0001                     /dev/mapper/mpatha                            ONLINE  Y
12 rows selected.
--以下操作均可以成功:
alter diskgroup ocrvt drop disk OCRVT_0003;
alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi';   
--如果不改参数，那么只能同时删除/增加每个failgroup中的成员:
alter diskgroup ocrvt drop disk OCRVT_0003, OCRVT_0004, OCRVT_0005;
alter diskgroup ocrvt add FAILGROUP OCRVT_0000 disk '/dev/mapper/mpathi'
FAILGROUP OCRVT_0001 disk '/dev/mapper/mpathj'
FAILGROUP OCRVT_0002 disk '/dev/mapper/mpathk';
--最后同样可以动态还原配置：
alter system set "_asm_disable_failgroup_size_checking"=false;
alter system set "_asm_disable_dangerous_failgroup_checking"=false;

注意：实验发现如果使用asmca添加磁盘，无论是否设置这个参数，都会报错[DBT-30003] The size of the disks selected is not the same as to allow for an equal number of 4MB AU size blocks.

而使用命令行操作，只要设置这2个隐藏参数为true即可成功。