File Transfer Protocol (FTP) has been the standard method for sharing files over the Internet for many years. Even with the popularity of the Web, which made document database services such as Gopher and WAIS almost obsolete, FTP servers are still the most common way to make directories of documents and software available to the public over the Internet.
File-sharing applications, such as NFS and Samba, are excellent tools for sharing files and directories over a private network. For organizations that need to share large numbers of files over public networks, however, FTP server software provides more robust tools for sharing files and protecting your computer systems. Also, FTP client software (for accessing FTP servers) is available for any type of computer that can access a network.
This chapter describes how to set up and maintain an FTP server, focusing on two FTP server packages: the Very Secure FTP Server software (vsFTPd) and the Washington University FTP Server software (WU-FTPD).
In recent versions of Red Hat Linux, the vsFTPd package has become the recommended FTP server software for Red Hat Linux. In fact, the WU-FTPD package has been dropped from the distribution. If you still want WU-FTPD as your FTP server, however, you can install the WU-FTPD package (from rpmfind.net or other sources) and use it on the current version of Red Hat Linux.
Configuring your FTP server to share private files or to allow users to upload files to your server involves more risks than just allowing downloads. See the end of this chapter for references to documents from CERT that provide FTP-security tips.