1.安装相关包
yum -y instll telnet-server
yum -y instll telnet
yum -y instll xinetd
2.设置开机自启动
systemctl enable xinetd.service
systemctl enable telnet.socket
3.启动服务
systemctl start telnet.socket
systemctl start xinetd（或service xinetd start）
yum -y instll telnet-server
yum -y instll telnet
yum -y instll xinetd
systemctl enable xinetd.service
systemctl enable telnet.socket
systemctl start telnet.socket
systemctl start xinetd（或service xinetd start）