查看系统中是否已经安装了Telnet客户端和服务端

rpm -qa | grep telent

然后检查yum列表里面有什么

[root@slave01 ~]# yum list | grep telnet
telnet-server.x86_64                       1:0.17-48.el6                 @base  
telnet.x86_64                              1:0.17-48.el6                 base 

安装

yum install -y telnet-server.x86_64
yum install -y telnet.x86_64

启动服务端

[root@localhost bin]# service telnet.socket start
Redirecting to /bin/systemctl start telnet.socket

查看是否启动

[root@localhost ~]# netstat -lntp | grep 23
tcp6       0      0 :::23                   :::*                    LISTEN      1/systemd   

联机

telnet 192.168.137.151
Kernel 3.10.0-1160.31.1.el7.x86_64 on an x86_64
localhost login: chendongpu
Password:
Last login: Mon Dec  6 12:44:21 from localhost
[chendongpu@localhost ~]$ ls
鍏叡  妯℃澘  瑙嗛  鍥剧墖  鏂囨。  涓嬭浇  闊充箰  妗岄潰