20.6. Requiring SSH for Remote Connections
20.6. Requiring SSH for Remote Connections For SSH to be truly effective, using insecure connection protocols, such as Telnet and FTP, should be prohibited. Otherwise, a user's password may be protected using SSH for one session, only to be captured later while logging in using Telnet. Some services to disable include: telnet rsh rlogin vsftpd To disable insecure connection methods to the system, use the command line program chkconfig , the ncurses-based program /usr/sbin/ntsysv , or the Services Configuration Tool ( system-config-services ) graphical application. All of these tools require root level access. For more information on runlevels and configuring services with chkconfig , /usr/sbin/ntsysv , and the Services Configuration Tool , refer to the chapter titled Controlling Access to Services in the System Administrators Guide .