Set ORACLE_SID to your +ASM instance.
[oracle@oel511g ~]$ sqlplus '/as sysasm'
SQL> select group_number,name from v$asm_diskgroup;
SQL> col PATH for a35GROUP_NUMBER NAME
------------ ------------------------------
1 DATA
SQL> select path,name from v$asm_disk where group_number=1;
SQL> alter diskgroup DATA drop disk DATA_0001;PATH NAME
----------------------------------- ------------------------------
/dev/oracleasm/disks/DATA2 DATA_0001
/dev/oracleasm/disks/DATA1 DATA_0000
SQL> commit;SQL> alter diskgroup DATA drop disk DATA_0001;
Diskgroup altered.
SQL>
column name format a20;
column path format a35
column mount_status format a12;
SET linesize 200;
SELECT name,
path,
group_number,
disk_number,
mount_status,
header_status,
state
FROM v$asm_disk
ORDER BY group_number;
NAME PATH GROUP_NUMBER DISK_NUMBER MOUNT_STATUS HEADER_STATU STATE
-------------------- ----------------------------------- ------------ ----------- ------------ ------------ --------
DATA_0000 /dev/oracleasm/disks/DATA1 1 0 CACHED MEMBER NORMAL
DATA_0001 /dev/oracleasm/disks/DATA2 1 1 CACHED MEMBER DROPPING
SQL> select * from v$asm_operation;
GROUP_NUMBER OPERA STAT POWER ACTUAL SOFAR EST_WORK EST_RATE EST_MINUTES ERROR_CODE
------------ ----- ---- ---------- ---------- ---------- ---------- ---------- ----------- --------------------------------------------
1 REBAL ERRS 11 ORA-15041
SQL> alter diskgroup DATA undrop disks;
SQL>SQL> alter diskgroup DATA undrop disks;
Diskgroup altered.
select disk_number "Disk #", free_mb
from v$asm_disk
where group_number = 1
order by 2;
Disk # FREE_MB
---------- ----------
0 8129
2 8129
1 8157
NAME PATH GROUP_NUMBER DISK_NUMBER MOUNT_STATUS HEADER_STATU STATE
-------------------- ----------------------------------- ------------ ----------- ------------ ------------ --------
/dev/oracleasm/disks/DATA5 0 0 CLOSED PROVISIONED NORMAL
/dev/oracleasm/disks/DATA4 0 1 CLOSED PROVISIONED NORMAL
/dev/oracleasm/disks/DATA3 0 2 CLOSED FORMER NORMAL
DATA_0001 /dev/oracleasm/disks/DATA2 1 1 CACHED MEMBER NORMAL
DATA_0000 /dev/oracleasm/disks/DATA1 1 0 CACHED MEMBER NORMAL
NAME PATH GROUP_NUMBER DISK_NUMBER MOUNT_STATUS HEADER_STATU STATE
-------------------- ----------------------------------- ------------ ----------- ------------ ------------ --------
/dev/oracleasm/disks/DATA5 0 0 CLOSED PROVISIONED NORMAL
/dev/oracleasm/disks/DATA4 0 1 CLOSED PROVISIONED NORMAL
DATA_0001 /dev/oracleasm/disks/DATA2 1 1 CACHED MEMBER NORMAL
DATA_0000 /dev/oracleasm/disks/DATA1 1 0 CACHED MEMBER NORMAL
FLASH_0000 /dev/oracleasm/disks/DATA3 2 0 CACHED MEMBER NORMAL
NAME PATH GROUP_NUMBER DISK_NUMBER MOUNT_STATUS HEADER_STATU STATE
-------------------- ----------------------------------- ------------ ----------- ------------ ------------ --------
DATA_0000 /dev/oracleasm/disks/DATA1 1 0 CACHED MEMBER NORMAL
DATA_0001 /dev/oracleasm/disks/DATA2 1 1 CACHED MEMBER NORMAL
FLASH_0001 /dev/oracleasm/disks/DATA4 2 1 CACHED MEMBER NORMAL
FLASH_0000 /dev/oracleasm/disks/DATA3 2 0 CACHED MEMBER NORMAL
FLASH_0002 /dev/oracleasm/disks/DATA5 2 2 CACHED MEMBER NORMAL
Create Disk Group:
SQL>
create diskgroup FLASH external redundancy disk '/dev/oracleasm/disks/DATA3';
Add Disk To A Disk Group:
SQL>
alter diskgroup DATA add disk 'ORCL:DATA08';
SQL> alter diskgroup DATA add disk 'ORCL:DATA08';
Diskgroup altered.