Setting Up an FTP Server Getting Started Guide 169 Setting Up an FTP Server An FTP server is configured and running after a standard OpenLinux installation. You can use anonymous FTP to exchange files with your OpenLinux system via any FTP client, including a Web browser. To try this, enter this URL from any cli- ent that can access your Linux system over a network: ftp://linux_system_name/ When you use this command, you are accessing the directory /home/ftp on your OpenLinux system. Any files that you place in the directory /home/ftp/pub are accessible by default to anonymous users who log in to your system using FTP. You can also use FTP to access regular user accounts. Use a URL like this one: ftp://username@linux_system_name/ You are prompted for a password before you see the files on the Linux system. Several files located in the /etc directory define the configuration of the FTP server running on OpenLinux. Although the default configuration is fairly secure, you should review the configuration files carefully before using FTP openly on an Internet-connected OpenLinux server. The following files are relevant to your FTP server: • /etc/inetd.conf: defines how FTP connection requests are processed by the TCP Wrapper program (see “Using TCP Wrappers” on page 165). • /etc/hosts.allow and /etc/hosts.deny: define who can access the FTP server (see“Using TCP Wrappers” on page 165). • /etc/ftpusers: defines regular users on your OpenLinux system who can- not use FTP (this is intended as a security protection) • /etc/ftpaccess: defines access rules for all user accounts, including the anonymous user • /var/log/xferlog: logs all transfers between FTP clients and your FTP server, both for regular and anonymous users. Creating a Mail Server OpenLinux includes the sendmail Mail Transfer Agent (MTA). This program makes your OpenLinux system a complete mail server. You can check that the sendmail package is installed using this command: