关闭selinux
[root@centos7 ~]#vim /etc/selinux/config
SELINUX=disabled
关闭防火墙
[root@centos7 ~]#systemctl stop firewalld
.=====================================================================.
[root@centos7 ~]#rpm -qi chrony //centOS7 上自带chrony
Name : chrony
Version : 3.2
Release : 2.el7
Architecture: x86_64
Install Date: Sun 09 Dec 2018 10:15:41 PM CST
Group : System Environment/Daemons
Size : 487489
License : GPLv2
Signature : RSA/SHA256, Wed 25 Apr 2018 06:55:05 PM CST, Key ID 24c6a8a7f4a80eb5
Source RPM : chrony-3.2-2.el7.src.rpm
Build Date : Fri 13 Apr 2018 01:38:53 AM CST
Build Host : x86-01.bsys.centos.org
Relocations : (not relocatable)
Packager : CentOS BuildSystem <http://bugs.centos.org>
Vendor : CentOS
URL : https://chrony.tuxfamily.org
Summary : An NTP client/server
Description :
A client/server for the Network Time Protocol, this program keeps your
computer‘s clock accurate. It was specially designed to support
systems with intermittent internet connections, but it also works well
in permanently connected environments. It can use also hardware reference
clocks, system real-time clock or manual input as time references.
[root@centos7 ~]#rpm -ql chrony
/etc/NetworkManager/dispatcher.d/20-chrony
/etc/chrony.conf //配置文件
/etc/chrony.keys
/etc/dhcp/dhclient.d/chrony.sh
/etc/logrotate.d/chrony
/etc/sysconfig/chronyd
/usr/bin/chronyc 时间同步服务 chrony
原文地址：http://blog.51cto.com/8845692/2350842