> 解决方法:
rpm -qa telnet-server
rpm -qa xinetd
yum list |grep telnet
telnet-server.x86_64 1:0.17-59.el7 @base
telnet.x86_64 1:0.17-59.el7 base
yum install telnet-server.x86_64
yum install telnet.x86_64
yum list |grep xinetd
xinetd.x86_64 2:2.3.15-12.el7 @base
yum install xinetd.x86_64
systemctl enable xinetd.service
systemctl enable telnet.socket
systemctl start telnet.socket
systemctl start xinetd(或service xinetd start)