Centos6.5安装telnet

1，检查是否已安装
  在安装Telnet前先检查系统是否安装了telnet-server和xinetd
  rpm -qa telnet-server
  rpm -qa xinetd
2，下载离线安装包
  xinetd-2.3.14-34.el6.x86_64.rpm
  telnet-server-0.17-47.el6.x86_64.rpm
  telnet-0.17-47.el6.x86_64.rpm
3，上传并安装
  rpm -ivh xinetd-2.3.14-34.el6.x86_64.rpm
  rpm -ivh telnet-server-0.17-47.el6.x86_64.rpm
  rpm -ivh telnet-0.17-47.el6.x86_64.rpm

4，配置开机启动
  配置Telnet，xinetd和telnet开机启动，否则无法启动Telnet服务
  systemctl enable xinetd.service
  systemctl enable telnet.socket

5，启动服务
  systemctl start telnet.socket
  systemctl start xinetd
6，配置防火墙规则
  firewall-cmd --permanent --add-port=23/tcp
  firewall-cmd --reload