1. Configure Network Time Protocol (NTP)
Before installation, you can prepare an excel form to record account passwords, because there will be many user passwords involved later, so you can record them in advance, such as this one. 
1.1 Introduction
to chrony First post the official website address. In fact, there are many softwares, and you can find detailed instructions on the official website.
https://chrony.tuxfamily.org/index.html
First of all, the full name of NTP is NTP (Network Time Protocol), which is a network time protocol used to synchronize the system clock. The official website mentions that the open source protocol is GPLv2, about the open source protocol For the explanation, here is a picture directly quoted from the great god Ruan Yifeng.
Chrony has two core components, the chronyd daemon, and the chronyc command-line interface program, which can be used to monitor the performance of chronyd and change various operating parameters during runtime.
Regarding the comparison between chrony and other time synchronization software, it is also available on the official website. Here I will cut some for you to see.
For example, here are some basic information comparisons, supported operating systems, open source licenses, languages, and operating sizes. If you are interested, you can go to the official website to find out.
1.2 Operation on the control node
First yum install
yum install chrony -y
edit chrony.conf
Vim /etc/chrony.conf The
first point to modify is: the synchronized server, I am here to modify it to
Aliyun server ntp1.aliyun.com The
second point of iburst is to modify the allowed client to the address of the computing node
Set boot up and start the service
systemctl enable chronyd.service
systemctl start chronyd.service
1.3 Operations on the compute node
First install
yum yum install chrony -y
Edit chrony.conf
Vim /etc/chrony.conf
Here you only need to modify a bit, modify the
server to the server of the control node 192.168.244.131 iburst
Set boot up and start the service
# systemctl enable chronyd.service
# systemctl start chronyd.service1.4 Verify
that chronyc sources are running on two nodes, this is to check the time synchronization source
