If the time between the app and DB server are off by even a little bit it causes DSP to show a red stoplight, appearing like nothing is working.
Normally this is solved by doing a time sync of the app and DB server to the same time source.
I recently ran into this at a customer site where both servers are in an Azure Zone and local to each other, however the DBA team changed the timezone of their server to be the "DBA's local timezone" instead of leaving it at the timezone of the server location. The app and DB server at this client have the same time source and are synced when looking at UTC for both servers.
I see this becoming a larger problem as more DSP Cloud systems are rolled out where the DB server is managed separately from the app server.