ASM Administration

Download ASM from Oracle.

Install ASM using Asmlib:


[root@eprax01 asm]# uname -a
Linux eprax01 2.6.9-78.ELsmp #1 SMP Wed Jul 9 15:39:47 EDT 2008 i686 i686 i386 GNU/Linux
[root@eprax01 asm]# rpm -Uvh oracleasmlib-2.0.4-1.el4.i386.rpm \
> oracleasm-support-2.1.3-1.el4.i386.rpm \
> oracleasm-2.6.9-78.ELsmp-2.0.5-1.el4.i686.rpm
Preparing... ########################################### [100%]
1:oracleasm-support ########################################### [ 33%]
2:oracleasm-2.6.9-78.ELsm########################################### [ 67%]
3:oracleasmlib ########################################### [100%]
[root@eprax01 asm]#


Configure ASM

[root@eprax01 ~]# /etc/init.d/oracleasm configure
Configuring the Oracle ASM library driver.

This will configure the on-boot properties of the Oracle ASM library
driver. The following questions will determine whether the driver is
loaded on boot and what permissions it will have. The current values
will be shown in brackets ('[]'). Hitting without typing an
answer will keep that current value. Ctrl-C will abort.

Default user to own the driver interface []: oracle
Default group to own the driver interface []: dba
Start Oracle ASM library driver on boot (y/n) [n]: y
Scan for Oracle ASM disks on boot (y/n) [y]: y
Writing Oracle ASM library driver configuration: done
Initializing the Oracle ASMLib driver: [ OK ]
Scanning the system for Oracle ASMLib disks: [ OK ]

Create ASM Disks

[root@eprax01 ~]# /etc/init.d/oracleasm createdisk DATA01 /dev/sdc1
Marking disk "DATA01" as an ASM disk: [ OK ]
[root@eprax01 ~]# /etc/init.d/oracleasm createdisk DATA02 /dev/sdb1
Marking disk "DATA02" as an ASM disk: [ OK ]
[root@eprax01 ~]# /etc/init.d/oracleasm listdisks
DATA01
DATA02

The initialization parameters that are of specific interest for an ASM instance are:




INSTANCE_TYPE - Set to ASM or RDBMS depending on the instance type. The default is RDBMS.

DB_UNIQUE_NAME - Specifies a globally unique name for the database. This defaults to +ASM but must be altered if you intend to run multiple ASM instances.

ASM_POWER_LIMIT -The maximum power for a rebalancing operation on an ASM instance. The valid values range from 1 to 11, with 1 being the default. The higher the limit the more resources are allocated resulting in faster rebalancing operations. This value is also used as the default when the POWER clause is omitted from a rebalance operation.

ASM_DISKGROUPS - The list of disk groups that should be mounted by an ASM instance during instance startup, or by the ALTER DISKGROUP ALL MOUNT statement. ASM configuration changes are automatically reflected in this parameter.

ASM_DISKSTRING - Specifies a value that can be used to limit the disks considered for discovery. Altering the default value may improve the speed of disk group mount time and the speed of adding a disk to a disk group. Changing the parameter to a value which prevents the discovery of already mounted disks results in an error. The default value is NULL allowing all suitable disks to be considered.

SQL> sho parameter ASM_DISKSTRING




NAME TYPE VALUE

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

asm_diskstring string


SQL> sho parameter ASM_POWER_LIMIT




NAME TYPE VALUE

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

asm_power_limit integer 1

SQL> select group_number,state,name,total_mb from v$asm_disk;



GROUP_NUMBER STATE NAME TOTAL_MB

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

1 NORMAL DATA01 2047

1 NORMAL DATA02 4094