How to fix the Oracle error ORA-15251: only restricted mount is allowed in the ASM instance?

In this post, you’ll learn more about the Oracle ErrorORA-15251: only restricted mount is allowed in the ASM instance with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-15251: only restricted mount is allowed in the ASM instance

Reason for the Error ORA-15251: only restricted mount is allowed in the ASM instance

The ASM instance was started in restricted mode, and an attempt was made to mount a diskgroup in non-restricted mode.

How to fix the Error ORA-15251: only restricted mount is allowed in the ASM instance ?

You can fix this error in Oracle by following the below steps

Start the ASM instance in non-restricted mode and mount the diskgroup again, or mount the diskgroup in restricted mode.