The text file
ftpusers contains a list of users that may not log in using the
File Transfer Protocol (FTP) server daemon. This file is used not merely for
system administration purposes but for improving security within a TCP/IP
networked environment. It will typically contain a list of the users that
either have no business using ftp or have too many privileges to be allowed
to log in through the FTP server daemon.
Such users usually include root, daemon, bin, uucp, and news.
If your FTP server daemon doesnt use
ftpusers then it is suggested that you read its documentation to find out how to
block access for certain users. Washington University FTP server Daemon
(wuftpd) and Professional FTP Daemon (proftpd) are known to make use of