Add Disk to ASM

1. Add disk in OS and setup the multipath.
2. Use lsblk to see the new disk (e.g. /dev/sde)
3. As root use fdisk /dev/sde to add a new partition (e.g. /dev/sde1)
4. As root use oracleasm (asmlib) or udev to make the disks available to ASM.
5. As grid connect to ASM instance and either create or alter the desired diskgroup with the new disk
   • alter diskgroup DATA add disk '/dev/sde1' NAME DATA_002 rebalance;
   • create diskgroup DATA2 add disk '/dev/sde1' NAME DATA_002 rebalance;
6. Check new size or new diskgroup from V$ASM_DISKG and V$ASM_DISKGROUP views.

Keep in mind that if normal or extended redundancy are used then additional disk must be added in each filegroup by using FAILGROUP clause.