Ubuntu实现远程登陆之telnet——安装telnet服务端

telnet是一种网络通信协议，我们可以使用它登录远程服务器，Ubuntu安装后默认只有telnet客户端，即只能在Ubuntu内去连接其他telnet服务器，本文将详细介绍在Ubuntu下安装部署telnet服务端，以便实现其他客户端使用telnet协议远程登录Ubuntu服务器。
环境：Ubuntu14.04
1.首先以root权限运行apt-get install xinetd,普通用户的执行命令是sudo apt-get install xinetd

mm@ubuntu:/media/mm/f019bb83-2870-44f4-a660-ff154efa1bee/linux_6ul/new_imx6ul/yanshou$ sudo apt install xinetd
sudo: /etc/sudoers.d is world writable
Reading package lists... Done
Building dependency tree       
Reading state information... Done
xinetd is already the newest version.
The following packages were automatically installed and are no longer required:
  libdbusmenu-gtk4 libqpdf13
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 4 not upgraded.

2.接着运行以root权限apt-get install telnet,普通用户的执行命令是sudo apt-get install telnet

mm@ubuntu:/media/mm/f019bb83-2870-44f4-a660-ff154efa1bee/linux_6ul/new_imx6ul/yanshou$ sudo apt install telnetd
sudo: /etc/sudoers.d is