安装过程中先查看服务器已有相关ntp的依赖，再视情况安装 centos7.664位NTP安装RPM软件包：ntp-4.2.6p5-28.el7.centos.x86_64.rpm、ntpdate-4.2.6p5-28.el7.centos.x86_64.rpm、autogen-libopts-5.18-5.el7.x86_64.rpm、openssl-1.0.2k-12.el7.x86_64.rpm、openssl-libs-1.0.2k-12.el7.x86_64.rpm