Quick post with the commands required to verify NTP configuration on a VMware Photon OS Appliance
ssh to the appliance as root
To check if the NTP service is up and running you can run this command
systemctl status systemd-timesyncd
If its stopped run this command
systemctl start systemd-timesyncd
To configure NTP servers run the following
vi /etc/systemd/timesyncd.conf
Add timeservers under [Time]
LifeOfBrianOC 