CREATE ASM DISKGROUP AFTER STORAGE ADDITION ORACLE
Basically there are two ways to create ASM diskgroup
- Manual (sqlplus)
- Automatic (ASMCA)
Check for available candidate disks
ASMCMD> lsdsk -p --candidate
Group_Num Disk_Num Incarn Mount_Stat Header_Stat Mode_Stat State Path
0 0 0 CLOSED PROVISIONED ONLINE NORMAL /dev/oracleasm/disks/DATA
0 2 0 CLOSED PROVISIONED ONLINE NORMAL /dev/oracleasm/disks/RECO
0 1 0 CLOSED PROVISIONED ONLINE NORMAL /dev/oracleasm/disks/REDO
Check for permissions on disks
[root@dgprim01 grid]# ls -lHL /dev/oracleasm/disks/
total 0
brw-rw----. 1 oracle oinstall 8, 33 Sep 2 20:04 DATA
brw-rw----. 1 oracle oinstall 8, 65 Sep 3 00:41 OCRVOD
brw-rw----. 1 oracle oinstall 8, 49 Sep 2 20:04 RECO
brw-rw----. 1 oracle oinstall 8, 81 Sep 2 20:04 REDO
Check for asm disks and their status
SQL> select NAME,GROUP_NUMBER,DISK_NUMBER,MOUNT_STATUS,HEADER_STATUS,PATH from v$asm_disk;
NAME GROUP_NUMBER DISK_NUMBER MOUNT_S HEADER_STATU PATH
-------------------- ------------ ----------- ------- ------------ --------------------
0 0 CLOSED PROVISIONED /dev/oracleasm/disks
/DATA
0 1 CLOSED PROVISIONED /dev/oracleasm/disks
/REDO
0 2 CLOSED PROVISIONED /dev/oracleasm/disks
/RECO
OCRVOD_0000 1 0 CACHED MEMBER /dev/oracleasm/disks
/OCRVOD
Create the diskgroups DATA and RECO by manual method using sqlplus
SQL> create diskgroup DATA external redundancy disk '/dev/oracleasm/disks/DATA';
Diskgroup created.
SQL> create diskgroup RECO external redundancy disk '/dev/oracleasm/disks/RECO';
Diskgroup created.
Create diskgroup using ASMCA as well (this step is optional as i show method of creating diskgroup only for redo diskgroup using ASMCA). Click on create

Give diskgroup name ,choose the available disk and click ok

Post the step, the diskgroup get created
