Add disk to ASM RAC

How to add disk to ASM (DATABASE) runing in production server

We have database running on ASM, after two years we faced the problem of space deficiency.

Now we planed to add disk to ASM diskgroup DATAGROUP.

SQL> @asm
NAME                 TOTAL_GB                FREE_GB
------------------------------ ---------- ----------
DATAGROUP            249.995117             15.2236328
IDXGROUP             149.99707              10.4892578

Steps are below

1) Create partition of disk /dev/sdm which we got new LUN from Storage

[root@rac-node1 ~]# fdisk -l /dev/sdm
Disk /dev/sdm: 85.8 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk /dev/sdm doesn't contain a valid partition table
[root@rac-node1 ~]# fdisk /dev/sdm
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.

The number of cylinders for this disk is set to 10443.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
 (e.g., DOS FDISK, OS/2 FDISK)
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): n
Command action
 e extended
 p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-10443, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-10443, default 10443):
Using default value 10443
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@rac-node1 ~]# fdisk -l /dev/sdm
Disk /dev/sdm: 85.8 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sdm1 1 10443 83883366 83 Linux
[root@rac-node1 ~]#

2) Configure the disk /dev/sdm1 to ASM and giving LABEL DATA5

[root@rac-node1 ~]# /etc/init.d/oracleasm createdisk DATA5 /dev/sdm1
Marking disk "DATA5" as an ASM disk: [ OK ]
[root@rac-node1 ~]# /etc/init.d/oracleasm scandisks
Scanning the system for Oracle ASMLib disks: [ OK ]
[root@rac-node1 ~]# /etc/init.d/oracleasm listdisks
DATA3
DATA4
DATA5
DISK1
DISK2
INDEX2
INDEX5
[root@rac-node1 ~]#

Scandisks on RAC -node2

[root@rac-node2 ~]# /etc/init.d/oracleasm scandisks
Scanning the system for Oracle ASMLib disks: [ OK ]
[root@rac-node2 ~]# /etc/init.d/oracleasm listdisks
DATA3
DATA4
DATA5
DISK1
DISK2
INDEX2
INDEX5

Add the disk to /etc/rawdevices

[root@rac-node2 bin]vi /etc/sysconfig/rawdevices

/dev/raw/raw6 /dev/sdm1    ==> add this to rawdevices file

And added to /etc/rc.local for permission on reboot

[root@rac-node2 bin]#vi /etc/rc.local

chmod 660 /dev/raw/raw6

Check the disk status 

SQL> set linesize 9999
SQL> ;
 SELECT
 NVL(a.name, '[CANDIDATE]') disk_group_name
 , b.path disk_file_path
 , b.name disk_file_name
 , b.failgroup disk_file_fail_group
 FROM
 v$asm_diskgroup a RIGHT OUTER JOIN v$asm_disk b USING (group_number)
 ORDER BY
* a.name
SQL> /
DISK_GROUP_NAME DISK_FILE_PATH DISK_FILE_NAME DISK_FILE_FAIL_GROUP
------------------------------ --------------
DATAGROUP       ORCL:DISK1 DISK1 DISK1
DATAGROUP       ORCL:INDEX5 INDEX5 INDEX5
DATAGROUP       ORCL:DATA4 DATA4 DATA4
DATAGROUP       ORCL:DATA3 DATA3 DATA3
IDXGROUP        ORCL:DISK2 DISK2 DISK2
IDXGROUP        ORCL:INDEX2 INDEX2 INDEX2
[CANDIDATE]    ORCL:DATA5 ==> this is the new disk 

7 rows selected.

3) Add disk DATA5 to diskgroup DATAGROUP

SQL> alter diskgroup DATAGROUP ADD DISK 'ORCL:DATA5' ;
Diskgroup altered.

Check disk status again

SQL> SELECT
 2 NVL(a.name, '[CANDIDATE]') disk_group_name
 , b.path disk_file_path
 , b.name disk_file_name
 3 4 5 , b.failgroup disk_file_fail_group
 6 FROM
 7 v$asm_diskgroup a RIGHT OUTER JOIN v$asm_disk b USING (group_number)
 8 ORDER BY
 9 a.name;
DISK_GROUP_NAME DISK_FILE_PATH ISK_FILE_NAME DISK_FILE_FAIL_GROUP
----------------------------------------------------------
DATAGROUP        ORCL:INDEX5 NDEX5 INDEX5
DATAGROUP        ORCL:DATA4 ATA4 DATA4
DATAGROUP        ORCL:DISK1 ISK1 DISK1
DATAGROUP        ORCL:DATA5 ATA5 DATA5
DATAGROUP        ORCL:DATA3 ATA3 DATA3
IDXGROUP         ORCL:INDEX2 NDEX2 INDEX2
IDXGROUP         ORCL:DISK2 ISK2 DISK2
7 rows selected. There is no candidates any more for DATA5

SQL> host cat script/asm.sql
select name,TOTAL_MB/1024 total_gb,free_mb/1024 FREE_GB from v$asm_diskgroup;
NAME             TOTAL_GB        FREE_GB
------------------------------ ---------- ----------
DATAGROUP       329.992188      95.21875
IDXGROUP        149.99707       10.4892578
SQL>

Completed.