https://www.server-world.info/en/note?os=SUSE_Linux_Enterprise_15&p=ntp&f=1
Install Chrony and Configure NTP server for time adjustment.
1.Install Chrony.
dlp:~ # zypper -n install chrony
2. Configure Chrony.
dlp:~ # vi /etc/chrony.conf # line 3: change servers for synchronization (replace to your timezone's one) # ! pool pool.ntp.org iburst server ntp.nict.jp iburst server ntp1.jst.mfeed.ad.jp iburst # line 25: add the network range you allow to receive requests allow 10.0.0.0/24 dlp:~ # systemctl start chronyd dlp:~ # systemctl enable chronyd
3.If Firewalld is running, allow NTP service. NTP uses 123/UDP.
dlp:~ # firewall-cmd --add-service=ntp --permanent success dlp:~ # firewall-cmd --reload success
4.Verify it works normally like follows.
dlp:~ # chronyc sources 210 Number of sources = 2 MS Name/IP address Stratum Poll Reach LastRx Last sample =============================================================================== ^* ntp-b3.nict.go.jp 1 6 17 11 -412us[-5299us] +/- 10ms ^- ntp1.jst.mfeed.ad.jp 2 6 17 12 +1433us[+1433us] +/- 87ms
dlp:~ # systemctl restart chronyd
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Configure NTP Client.
1. The settings of NTP Client on SUSE are mostly the same with Server's settings, so refer to Chrony Settings. For different settings from Server's one, Clients don't need to receive time synchronization requests from other computers, so it does not need to set access permission.
2. If you don't use NTP service daemon but use a command to sync time at once, run like follows.
# sync time dlp:~ # chronyc makestep 200 OK