In this article we will be creating new ASM diskgroup using SQLPLUS command while connected to ASM instance.
You must have an unused partition / disk on the server that can be used to create ASM diskgroup.
In this activity, we are going to use /dev/sdb4 and /dev/sdb5 to create a new normal redundancy disk group which needs at least two failure groups.
first check at OS level if you see those two partitions. Use below command to check
# fdisk –l
Mark the disk headers using the oracleasm utility as root user. You need to create ASM disks only from one node
# oracleasm createdisk RMANVOL1 /dev/sdb4 # oracleasm createdisk RMANVOL2 /dev/sdb5
Scan and list the ASM disks from node 1. If successful, you must be able to see the ASM disks on other nodes too
# oracleasm scandisks # oracleasm listdisks
Now that we have marked our ASM disks, we need to create a normal redundancy diskgroup using these two disks. Connect to the oracle user and make sure Oracle Home is set to Grid Home and Oracle SID is set to ASM1 (for node 1)
# sqlplus / as sysasm SQL> CREATE DISKGROUP RMANVOL NORMAL REDUNDANCY FAILGROUP failgrp1 DISK ‘/dev/sdb4’, FAILGROUP failgrp2 DISK ‘/dev/sdb5’;
Check the disk & its status
SELECT PATH, HEADER_STATUS, NAME FROM V$ASM_DISK;
Check the disk group & its status
SELECT NAME, STATE FROM V$ASM_DISKGROUP;
Mount the disk groups from other nodes
SELECT INST_ID, NAME, STATE FROM GV$ASM_DISKGROUP; ALTER DISKGROUP RMANVOL MOUNT; SELECT INST_ID, NAME, STATE FROM GV$ASM_DISKGROUP;