We had an issue where the time service on our vm host stopped and thus our domain controller that is acting as our NTP server getting it's time from .gov and all on premise machines getting their time go to were getting bad time given the server wasn't updating.
I am wondering if there is a way to setup a secondary NTP server that in cases where the primary were to be off the secondary would sync with it or take over. I'm not sure this would work as the clients didn't know the server's time was wrong so adjusted to the wrong time accordingly but had it not been a simple service restart wanted to see what others do so we have a solid backup plan going forward.
Servers and Clients --------> DC1 NTP --------------------------> time-a.nist.gov
DC2 backup to DC1 for DNS only no DHCP on this as this is an empty root.