1. nano /etc/systemd/timesyncd.conf

2. edit File
[Time]
NTP=dc1.domain.net dc2.domain.net
FallbackNTP=at.pool.ntp.org

3. Test
timedatectl

4. Like set Timezone
timedatectl set-timezone 'Europe/Vienna'

5. Service neustarten
service systemd-timesyncd restart

6. Zeit sync ?
service systemd-timesyncd status