Cause: ASM was unable to find a sufficient number of disks belonging to the diskgroup to continue the operation. See the solution below.

Error solution: Check that the disks in the diskgroup are present and functioning, that the owner of the ORACLE binary has read/write permission to the disks, and that the ASM_DISKSTRING initialization parameter has been set correctly. Verify that ASM discovers the appropriate disks by querying V$ASM_DISK from the ASM instance.