The Chrony is a default NTP (Network Time Protocol) client as well as an NTP server on RHEL / CentOS 8.

Table of Contents

1. Check Current Time
2. Install Chrony
3. Check Time Again
4. Config NTP Client

Check Current Time

At first, let’s check the current date & time:

timedatectl

You’ll see the output like:

               Local time: Fri 2020-03-20 13:26:10 +06
           Universal time: Fri 2020-03-20 07:26:10 UTC
                 RTC time: Fri 2020-03-20 07:20:10
                Time zone: Asia/Dhaka (+06, +0600)
System clock synchronized: no
              NTP service: no
          RTC in local TZ: no

The System clock synchronized & the NTP service’s value is no.

Install Chrony

Chrony is available in the DNF package manager. Just run this command to install Chrony:

sudo dnf install -y chrony

After installing Chrony, we need to start & enable:

# start
systemctl start chronyd

# enable
systemctl enable chronyd

We can check the status of Chrony using this command:

systemctl status chronyd

Check Time Again

Let’s check the time again:

timedatectl

Output:

               Local time: Fri 2020-03-20 13:20:10 +06
           Universal time: Fri 2020-03-20 07:20:10 UTC
                 RTC time: Fri 2020-03-20 07:20:10
                Time zone: Asia/Dhaka (+06, +0600)
System clock synchronized: yes
              NTP service: active
          RTC in local TZ: no

Now our server is showing the correct date & time. The System clock synchronized is yes & the NTP service’s value is active.

Config NTP Client

If you don’t know about the NTP client, you can skip this.

If you want to NTP client, open /etc/chrony.conf with your favorite editor:

sudo nano /etc/chrony.conf

To configure a system as an NTP client, it needs to know which NTP servers it should ask for the current time. You can specify the servers using the pool or server directive.

Comment out the default NTP servers and set your server IP address:

# Please consider joining the pool (http://www.pool.ntp.org/join.html).
# pool 2.centos.pool.ntp.org iburst
server YOUR_SERVER_IP

Save the file and restart Chrony:

sudo systemctl restart chronyd

Check for NTP server sources. Your local NTP server should be listed:

chronyc sources

Check NTP client list on the NTP server:

chronyc clients

To know more about Chrony, run this command:

man chronyc

That’s all. Thank you.