NTP Server : Configure NTP Server (Chrony)2025/04/21

	Install Chrony and Configure NTP server for time adjustment. NTP uses 123/UDP.
[1]	Install and Configure Chrony.

root@dlp:~#

apt -y install chrony

root@dlp:~#

vi /etc/chrony/chrony.conf

# add to last line : add network range you allow to receive time syncing requests from clients

allow 10.0.0.0/24

root@dlp:~#

mv /etc/chrony/sources.d/ubuntu-ntp-pools.sources /etc/chrony/sources.d/ubuntu-ntp-pools.sources.org

root@dlp:~#

vi /etc/chrony/sources.d/ntp-server.sources

# create new : add NTP server pool you like to use
pool ntp.nict.jp iburst

root@dlp:~#

systemctl restart chrony

# verify status

root@dlp:~#

chronyc sources

MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
^- ntp-b2.nict.go.jp             1   6     7     0   +187us[-1339us] +/-   11ms
^* ntp-b3.nict.go.jp             1   6     7     0   +154us[-1372us] +/-   10ms
^- ntp-a2.nict.go.jp             1   6     7     0  +1268us[ -259us] +/-   10ms
^- ntp-k1.nict.jp                1   6     7     0   +645us[ -882us] +/- 6876us

Matched Content