My environment is a Debian 11 server ( bullseye ). As it is a test system I kept DHCP configuration on the interface as well as the DHCP server is configured to give always to same IP address based on the MAC address. I realised that the NTP daemon restarts exactly in a 12 hour interval. This happens when the Debian server sends out a DHCP requests and gets immediately a DHCP ack. As it is a renewal after 50% of the lease time the IP address of the interface is unchanged. In daemon.log I can find
ntpd exiting on signal 15 (Terminated)
Immediately after that ntpd is restarted, obviously with systemctl functionality. I tried to figure out which script is responsible for this strange behaviour ( why should we restart ntpd if the lease is renewed. )
The files in
/etc/dhcp and below were promising. But I couldn't manage to stop this behaviour.
Any idea how to fix this issue ? Of course I could define fixed IP addresses for this network card but this would be the last way out.