Q. How do I install and turn on telnet server on Debian Linux VPS Server?
A. I don’t recommend using telnet at all on VPS or any other Linux / UNIX server. Telnet transfers all data including passwords in clear text format. It is recommended that you use ssh which is installed by default.
In case you still need telnet, type the following two commands (not recommended
# apt-get install telnetd
# /etc/init.d/inetd restart
$ telnet server-ip-address