For asm disks owner should be oracle:dba
You need to setup udev rules or edit rc.local
else after reboot permissions will change back to root
There are 2 methods to do it. Oracle recommends setting up UDEV
Here is alternative to udev
vi /etc/rc.local
#!/bin/bash
# THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES
#
# It is highly advisable to create own systemd services or udev rules
# to run scripts during boot instead of using this file.
#
# In contrast to previous versions due to parallel execution during boot
# this script will NOT be run after all other services.
#
# Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure
# that this script will be executed during boot.
touch /var/lock/subsys/local
chown oracle:dba /dev/mapper/mpatha
chown oracle:dba /dev/mapper/mpathb
chown oracle:dba /dev/mapper/mpathc
chmod 660 /dev/mapper/mpatha
chmod 660 /dev/mapper/mpathb
chmod 660 /dev/mapper/mpathc
After that check status of service. If its not enabled enable it
systemctl status rc-local.service
systemctl enable rc-local
systemctl start rc-local
2nd method using UDEV
#############preparing disks for ASM
/usr/lib/udev/scsi_id -g -u -d /dev/sdc
3624a93707784b3a3c17b437c00011074
/usr/lib/udev/scsi_id -g -u -d /dev/sdd
3624a93707784b3a3c17b437c0001106f
/usr/lib/udev/scsi_id -g -u -d /dev/sde
3624a93707784b3a3c17b437c00011071
vi /etc/scsi_id.config
options=-g
wq!
vi /etc/udev/rules.d/99-asmdevices.rules
KERNEL=="sd?1", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id -g -u -d /dev/$parent", RESULT=="3624a93707784b3a3c17b437c00011074", SYMLINK+="asm-disk1", OWNER="oracle", GROUP="dba", MODE="0660"
KERNEL=="sd?1", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id -g -u -d /dev/$parent", RESULT=="3624a93707784b3a3c17b437c0001106f", SYMLINK+="asm-disk2", OWNER="oracle", GROUP="dba", MODE="0660"
KERNEL=="sd?1", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id -g -u -d /dev/$parent", RESULT=="3624a93707784b3a3c17b437c00011071", SYMLINK+="asm-disk3", OWNER="oracle", GROUP="dba", MODE="0660"
##############Load rules
/sbin/partprobe /dev/sdc1
/sbin/partprobe /dev/sdd1
/sbin/partprobe /dev/sde1
##################Test rules
udevadm test /block/sdc/sdc1
udevadm test /block/sdd/sdd1
udevadm test /block/sde/sde1
#################Restart UDEV Service
udevadm control --reload-rules
check permissions
cd /dev
ls -lHL /dev/tas*
chown -R oracle:dba asm-disk1
chown -R oracle:dba asm-disk2
chown -R oracle:dba asm-disk3
chmod 660 asm-disk1
chmod 660 asm-disk2
chmod 660 asm-disk3
ls -lHL /dev/asm*
