Incremental backup using snapshot difference is not supported
for Data ONTAP file server version 'version.modification.submodification'.
Upgrade the file server 'file-server-name' to Data
ONTAP version '7.3' or later in order to perform incremental backup
operations using snapshot difference.
Explanation
The file server specified is not at the Data ONTAP version that
supports snapshot difference API.
System action
User response
Upgrade the file server to Data ONTAP version 7.3 or later and
retry the operation.