System and method of verifying validity of a metadata modification request to prevent improper metadata operations. During initialization of a volume in a storage device and once a metadata area is reserved for a metadata structure, information characterizing the metadata structure and metadata area is stored in the storage device, which may be in the form of an area legend composed of descriptors such as a magic signature, a node size, a clump size of reservation, and extent of the metadata area. Responsive to a request for operating on metadata, relevant information provided in the request is verified against the stored characteristic information. If the verification discovers an inconsistency between the information provided in the request and the stored characteristic information, the request modification is treated as invalid and blocked from operation.