- 在终端输入命令：sudo apt-get install xinetd telnetd
- 使用vim命令模式修改环境变量
（1）输入sudo vi /etc/inetd.conf
加入一行：telnet stream tcp nowait telnetd /usr/sbin/tcpd /usr/sbin/in.telnetd
按ESC将回到命令模式。再输入：wq 保存并退出编辑器。
（2）输入sudo vi /etc/xinetd.conf
加入：
#Simple configuration file for xinetd
#Some defaults, and include /etc/xinetd.d/
defaults
{
#Please note that you need a log_type line to be able to use
log_on_success
#and log_on_failure. The default is the following :
#log_type = SYSLOG daemon info
instances = 60
log_type = SYSLOG authpriv
log_on_success = HOST PID
log_on_failure = HOST
cps = 25 30
}
includedir /etc/xinetd.d
按ESC将回到命令模式。再输入：wq 保存并退出编辑器。
（3）输入sudo vi /etc/xinetd.d/telnet
再加入:
#default: on
#description: The telnet server serves telnet sessions; it uses
#unencrypted username/password pairs for authentication.
service telnet
{
disable = no
flags = REUSE
socket_type = stream
wait = no
user = root
server = /usr/sbin/in.telnetd
log_on_failure += USERID
}
按ESC将回到命令模式。再输入：wq 保存并退出编辑器。
3. 重启ubuntu或重启网络服务sudo /etc/init.d/xinetd restart