On OES 25.1

ps -ef | grep -i ntp
root     20700 20491  0 11:55 pts/0    00:00:00 grep --color=auto -i ntp  --> no ntp runs

lsof -i:123   --> standart port of ntp protokoll - no ntp runs

lsof -i:323
COMMAND  PID   USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
chronyd 2164 chrony    5u  IPv4  22402      0t0  UDP localhost:323
chronyd 2164 chrony    6u  IPv6  22403      0t0  UDP localhost:323

Since SLES 15 chrony is the default time protokoll Hint https://www.microfocus.com/documentation/open-enterprise-server/2023/mig_tools_lx/bimy7mx.html

/etc/chrony.conf --> configuration file

manpage: man chronyd --> Explanation of clie command, configuration and notes and explanations of the display of the Cli commands

cli commands

chronyc tracking
Reference ID    : C0A80A15 (myserver.mydomain.com)
Stratum         : 4
Ref time (UTC)  : Wed Feb 05 11:10:14 2025
System time     : 0.000001268 seconds slow of NTP time
Last offset     : +0.000007002 seconds
RMS offset      : 0.000057062 seconds
Frequency       : 86.138 ppm slow
Residual freq   : +0.002 ppm
Skew            : 0.256 ppm
Root delay      : 0.027543491 seconds
Root dispersion : 0.007205116 seconds
Update interval : 65.2 seconds
Leap status     : Normal

chronyc sources
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
^* myserver.mydomain.com             3   6   377    45    +70us[  +83us] +/-   26ms

The hint about port 323 in the firewall is an important thing if 323 is needed inbound. In this case, however, it is the chronyd client that is listening and therefore the port does not need to be running from the outside to the inside. An exception is if a chrony server is to run on an OES, in which case the port must be opened.

To summarize. In OES 2023 and higher ntp uses the chrony service. The service uses a different port than the ntp service. (123)

Greetings George