Several years ago I posted on Celerra/VNX NAS file extension filtering (see here), but didn’t write about file system reservations for specific file types, which is also possible. You can set up NAS shares so that only the file types you want stored there can be written to the share.
In order to do this, first navigate to the \\NAS_Server\C$ administrative share and open the “.filefilter” folder. You’ll then want to create the following filter files to complete the configuration:
allfiles[@<sharename>][@NetBIOS_name] – this filter file prohibits all file types from being created on the share. File types that you want excluded from this blanket deny are identified by regular filter files.
noext[@<sharename>][@NetBIOS_name] – this filter file prohibits files with no extensions from being created on the share. It will prevent a user from saving a file with no filename extension.
<extension_name>[@<sharename>][@NetBIOS_name] – this filter file identifies the types of files you want allowed on the share. You will need to configure the ACLs to identify which users and/or groups can create files on the share. File types specified by regular filter files like this one are the exceptions to the allfiles restriction. If you wanted to reserve a share for only outlook files and message files, you could create two filter files, pst[@<sharename>][@NetBIOS_name] and msg[@<sharename>][@NetBIOS_name], then set appropriate permissions.