[Oracle RAC ASM] Adding and removing disks in ASM

1/ To add new disk to ASM DISKGROUP. We use one among these commands depend on your case.

ALTER DISKGROUP FRA01 ADD FAILGROUP FAILGROUPA DISK '/ASMDISKS/ASMDISKA28';

ALTER DISKGROUP FRA01 ADD DISK '/DEVICES/ASMDISKA28' REBALANCE POWER 5 WAIT;

ALTER DISKGROUP FRA01 ADD DISK '/DEVICES/ASMDISKA28' FORCE;

ALTER DISKGROUP FRA01 ADD DISK

     '/DEVICES/ASMDISKA28' NAME ASMDISKA28,

     '/DEVICES/ASMDISKA29' NAME ASMDISKA29;

2/ To drop Disk from ASM DISKGROUP. We use one among these commands depend on your case. Note: Oracle recommend that is best if we using command drop and add (replace) will for best balance and performance.

ALTER DISKGROUP DATA01 DROP DISK ASMDISKA28;

ALTER DISKGROUP DATA01 DROP DISK ASMDISKA28 ADD FAILGROUP FAILGRP1 DISK '/DEVICES/ ASMDISKA29' NAME ASMDISKA29;

3/ These commands to view status:

SELECT GROUP_NUMBER, DISK_NUMBER, NAME, TOTAL_MB, FREE_MB, PATH FROM V$ASM_DISK
SELECT DISK_NUMBER, NAME, FAILGROUP, GROUP_NUMBER FROM V$ASM_DISK WHERE GROUP_NUMBER=3 ORDER BY NAME;
SELECT DISK_NUMBER, NAME, FAILGROUP, GROUP_NUMBER FROM V$ASM_DISK;

SELECT GROUP_NUMBER,NAME FROM V$ASM_DISKGROUP;