ORA-15395
file group redundancy incompatible with file type
Cause
An attempt was made to move a file to a file group with an incompatible redundancy specification, or to change the redundancy specification of a file group in a way that was incompatible with existing files in that file group.
Action
Specify a valid redundancy property for the file group. Only write-once files, such as the offline archive log and backup set, support parity protection. Other types of files must be configured with as unprotected, mirror or high redundancy. The file group redundancy can be changed from a parity protection scheme to unprotected, mirror, or high, and conversely, as long as the file group does not contain any files.