Oracle ASM

Set Environment variables
export ORACLE_HOME=opt/grid --ensure it is correct ASM home directory
export ORACLE_SID=+ASM1 --select * from V$ASM_CLIENT;

Note: Ensure that you set the correct ASM home directory.

You can look for ASM instance name at direcorty of logs like in this example /opt/oracle/diag/asm/+asm/+ASM1

Connect to the ASM instance

sqlplus / as sysasm

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create pfile from spfile;

/opt/grid/dbs/init+ASM1.ora

+ASM1.asm_diskgroups='DISK01'#Manual Dismount

*.asm_diskstring='/dev/sd*'

*.asm_power_limit=1

*.diagnostic_dest='/opt/oracle'

*.instance_type='asm'

*.large_pool_size=12M

*.remote_login_passwordfile='EXCLUSIVE'

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ASM diskgroups

SELECT name, type, total_mb, free_mb, required_mirror_free_mb,  usable_file_mb FROM V$ASM_DISKGROUP;

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ASM disks

SELECT name, header_status, path FROM V$ASM_DISK;

DISK01_0000 |  MEMBER  | /dev/sda DATA00_0000 | MEMBER  | /dev/sdd DATA00_0001 | MEMBER  | /dev/sde DATA00_0002 | MEMBER  | /dev/sdf   | CANDIDATE | /dev/sdc   | CANDIDATE | /dev/sdb 

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SQL> show parameter asm  NAME                                 TYPE        VALUE ------------------------------------ ----------- ------------------------------ asm_diskgroups                       string      DISK01 asm_diskstring                       string      /dev/sd* asm_power_limit                      integer     1 asm_preferred_read_failure_groups    string 

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Mount / Dismount the ASM diskgroup

ALTER DISKGROUP DISK02 MOUNT

ALTER DISKGROUP DISK01 DISMOUNT 

ALTER DISKGROUP ALL MOUNT

ALTER DISKGROUP ALL ENABLE VOLUME ALL

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ALTER DISKGROUP DISK02 ADD DISK      '/dev/sdc' NAME DISK_0001,      '/dev/sdb' NAME DISK_0002;

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http://docs.oracle.com/cd/B28359_01/server.111/b31107/asmdiskgrps.htm

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