When Apex One detects that an FTP client is attempting to upload files to an FTP server, it checks for the presence of data identifiers in the files. No file has been uploaded at this point. Depending on the DLP policy, Apex One will allow or block the upload.
When you configure a policy that blocks file uploads, remember the following:
When Apex One blocks an upload, some FTP clients will try to re-upload the files. In this case, Apex One terminates the FTP client to prevent the re-upload. Users do not receive a notification after the FTP client terminates. Inform them of this situation when you roll out your DLP policies.
If a file to be uploaded will overwrite a file on the FTP server, the file on the FTP server may be deleted.
For a list of supported FTP clients, see the Data Protection Lists document at:
http://docs.trendmicro.com/en-us/enterprise/data-protection-reference-documents.aspx