I have (2) ESXi 6.7 hosts setup to use the same NTP server (time.nist.gov). One host keeps the time fine, even though sometimes the logs will display a warning that it has lost connection to the NTP server. The other host loses time gradually. When I noticed the problem, I simply restarted the NTP Daemon and the time was corrected and in sync with the first host.
One week later, there is a 5 second difference between the 2 hosts. The NTP service is configured exactly the same on both hosts. Any suggestions on what I should try next? I figured I'd try the forums before contacting support.