Enable telnet service in ubuntu linux 18.04

1.run command in terminal

sudo apt-get install xinetd telnetd 

2.edit  /etc/inetd.conf file from this commad

sudo nano  /etc/inetd.conf

3.add these lines and save 

telnet stream tcp nowait telnetd /usr/sbin/tcpd /usr/sbin/in.telnetd

4.Edit /etc/xinetd.conf,make its content look like following:

    delete defaults section of code and add this 

service telnet
{
disable = no
flags = REUSE
socket_type = stream
wait = no
user = root
server = /usr/sbin/in.telnetd
log_on_failure += USERID
} 

5.Use this command to start telnet server:

sudo /etc/init.d/xinetd restart     

your service has started