How To Configure NTP Time Synchronization on Ubuntu Server

In today’s digital world, maintaining accurate time synchronization across all servers and systems is crucial for many operations. One way to ensure this is by using the Network Time Protocol (NTP). In this guide, we will walk you through the steps to configure NTP time synchronization on an Ubuntu server.

What is NTP?

NTP, or Network Time Protocol, is an internet protocol used to synchronize the clocks of computers to some time reference. It provides accurate and synchronized time across all servers and services in your infrastructure, which is essential for many system processes and tasks.

Prerequisites

Before we start, make sure you have:

• A running Ubuntu server
• Sudo or root access to the server

Step 1: Installing NTP

The first step in configuring NTP on your Ubuntu server is to install the NTP package. Open your terminal by pressing Ctrl+Alt+T and run the following command:

sudo apt-get install ntp

This command uses the apt-get package manager to install the NTP package. The sudo command is used to run the command with root privileges.

Step 2: Configuring NTP

Once the NTP package is installed, you need to configure it to use the desired NTP server. To do this, open the NTP configuration file using the nano text editor by running:

sudo nano /etc/ntp.conf

In this file, you will see a list of servers. These are the NTP servers that your system will synchronize with. You can choose to use the default Ubuntu servers, or you can specify your own. To specify your own, comment out the default servers by adding a # in front of them, then add your desired server. For example:

# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
#pool 0.ubuntu.pool.ntp.org iburst
#pool 1.ubuntu.pool.ntp.org iburst
#pool 2.ubuntu.pool.ntp.org iburst
#pool 3.ubuntu.pool.ntp.org iburst
server your.ntp.server

You can find a list of public NTP servers based on your location at pool.ntp.org.

After making the changes, save and close the file by pressing Ctrl+X, then Y to confirm saving the changes, and finally Enter to exit.

Step 3: Activating the Changes

To apply the changes, you need to restart the NTP service. Run the following command:

sudo service ntp restart

This command stops the NTP service and then starts it again with the new configuration.

Step 4: Verifying the Synchronization

To verify that the synchronization is successful, you can use the ntpq command. Run:

sudo ntpq -c lpeer

This command will display a list of all the servers that your system is synchronized with, along with their last checked times.

Step 5: Firewall Configuration

If you have a firewall enabled, you need to allow NTP traffic. This is done by opening UDP port 123. The command to do this depends on the firewall you are using. For UFW, you can use:

sudo ufw allow 123/udp

This command tells the firewall to allow incoming and outgoing traffic on UDP port 123, which is the port used by NTP.

Conclusion

By following these steps, you should now have a fully configured NTP service on your Ubuntu server. This will ensure that your server’s clock is always accurate, which is essential for many system tasks and operations. Remember to regularly check the synchronization status to ensure that everything is working as expected.