ORA-27041: unable to open file in ASM

 Error:

ORA-27041: unable to open file

Cause:
Unable to start the database after adding new disk in diskgroup.

Solution:

1. Check the permission of the disks.
Note: Need permission at OS level is 660 permissions:

oracle@RAC1 $ ls -ltra ../../devices/scsi_vhci/disk@g6000b5d0006a6a085f006f0000:a,raw
crw-r----- 1 grid asmadmin 30, 3008 Jul 4 16:39 ../../devices/scsi_vhci/disk@g6000b5d0006a0000006a085f006f0000:a,raw


2. Shutdown the database and cluster register service(CRS):

crsctl stop cluster -n RAC1


3. Change the permission of ASM disk

chmod 660 ../../devices/scsi_vhci/disk@g6000b5d0006a6a085f006f0000:a,raw


4. Start the CRS on affected Node.

crsctl start cluster -n RAC1