How to configure ntp server on CentOS8?

server 0.centos.pool.ntp.org iburst
server 1.centos.pool.ntp.org iburst
server 2.centos.pool.ntp.org iburst

Then add this line to allow your LAN clients to sync:

allow 192.168.0.0/16

You can change the subnet to match your network.

Also make sure local stratum is enabled so your server can serve time if it’s offline:

local stratum 10

Save and close the file.

Step 3 – Restart and Verify the Server

Restart the chrony daemon:

sudo systemctl restart chronyd

Check server status:

chronyc sources

This will show the current time sources and sync status.

Step 4 – Allow NTP Through the Firewall

If firewalld is enabled, open the NTP port:

sudo firewall-cmd --permanent --add-service=ntp
sudo firewall-cmd --reload

Step 5 – Confirm NTP Clients Can Sync

On a client machine, point it to your new NTP server:

sudo chronyc add server your-server-ip

Or modify the client’s /etc/chrony.conf to include:

server your-server-ip iburst

Then restart chrony on the client:

sudo systemctl restart chronyd

Check sync status from client:

chronyc tracking