Oracle Error Message
ORA-15307: disk string not discoverable by CSS; diskgroup string has CSS voting files
Reason for the Error
An attempt was made to add a disk which cannot be discovered by Cluster Synchronization Services (CSS). CSS has voting files in the disk group and will not be able to use the new disk if CSS cannot discover the disks.
Solution
Update the Automatic Storage Management (ASM) disk string in the Grid Plug and Play (GPnP) profile to include the specified disk and retry the operation. Alternatively, migrate the CSS voting files out of the diskgroup and retry the operation
