Sometimes, you can't use NTP to adjust your server time, you can change it by a command line.
[root@rac1 ~]# date -s '2017-02-18 17:30:00'
Sat Feb 30 17:30:00 CST 2017
The option "s" is set the time by its following string.
[root@rac1 ~]# date
Sat Feb 30 17:30:12 CST 2017
Chances are, you may need to change a bunch of server at the same time, you can use terminal tools to achieve this, like putty cm or mintty.