http://www.rpmfind.net/linux/RPM/index.html

-先检测这些软件包是否已经安装

rpm -qa | grep telnet

rpm -qa | grep telnet-server

rpm -qa | grep xinetd

-找到对应的版本下载

telnet：http://up.htmltoo.com/src/common/telnet/telnet-0.17-66.el7.x86_64.rpm

telnet-server：http://up.htmltoo.com/src/common/telnet/telnet-server-0.17-66.el7.x86_64.rpm

xinetd：http://up.htmltoo.com/src/common/telnet/xinetd-2.3.15-14.el7.x86_64.rpm

-卸载rpm包（如果已经安装了，又不清楚顺序，可以都卸载后统一安装）

rpm -e telnet-0.17-64.el7.x86_64

rpm -e telnet-server-0.17-64.el7.x86_64

rpm -e xinetd-2.3.15-14.el7.x86_64.rpm

-安装顺序：xinetd –> telnet –> telnet-server

rpm -ivh xinetd-2.3.15-14.el7.x86_64.rpm

rpm -ivh telnet-0.17-66.el7.x86_64.rpm

rpm -ivh telnet-server-0.17-66.el7.x86_64.rpm

-检查安装结果

rpm -qa | grep telnet

rpm -qa | grep telnet-server

rpm -qa | grep xinetd

-telnet服务之后,默认是不开启服务

vim /etc/xinetd.d/telnet

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

-重启xinetd

service xinetd restart

systemctl restart xinetd.service

或者

systemctl start xinetd

systemctl status xinetd

-查看xinetd是否重启成功

ps -ef | grep xinetd

-测试telnet是否安装成功

telnet 127.0.0.1