很多时候Linux操作系统都是在虚拟机中安装的，经常需要关机开机，这时候就可能导致系统的时间不正确了。我们可以使用ntpdate这个命令来同步系统时间。
如果没有这个命令的话需要安装ntpdate这个包：
[root@kandiannet fanxiaomo520]# yum install ntpdate Loaded plugins: product-id, subscription-manager This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register. Setting up Install Process base | 3.7 kB 00:00 data_myyumsource | 4.1 kB 00:00 ... extras | 3.4 kB 00:00 extras/primary_db | 29 kB 00:00 updates | 3.4 kB 00:00 updates/primary_db | 4.7 MB 00:00 Resolving Dependencies --> Running transaction check ---> Package ntpdate.x86_64 0:4.2.6p5-12.el6.centos.1 will be installed --> Finished Dependency Resolution Dependencies Resolved ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: ntpdate x86_64 4.2.6p5-12.el6.centos.1 updates 79 k Transaction Summary ================================================================================ Install 1 Package(s) Total download size: 79 k Installed size: 123 k Is this ok [y/N]: y Downloading Packages: ntpdate-4.2.6p5-12.el6.centos.1.x86_64.rpm | 79 kB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : ntpdate-4.2.6p5-12.el6.centos.1.x86_64 1/1 Verifying : ntpdate-4.2.6p5-12.el6.centos.1.x86_64 1/1 Installed: ntpdate.x86_64 0:4.2.6p5-12.el6.centos.1 Complete!
然后同步并写入硬件时钟：
[root@kandiannet fanxiaomo520]# ntpdate time.windows.com && hwclock -w 1 Nov 18:54:08 ntpdate[4337]: step time server 52.168.138.145 offset 99646.910274 sec [root@kandiannet fanxiaomo520]# date Wed Nov 1 18:54:19 CST 2017
原文链接：使用ntpdate命令同步系统时间，转载请注明来源！
