I have 2 servers on a LAN that I want to precisely synchronize. the goal is to have a time difference < 500 microseconds, constant, with no drift (from what I've found on the web, this is achievable accuracy).
those two servers must also have "correct" time but the accuracy is less important (within 1 second of the "real" time is acceptable). the "official" time servers are only accessible through a WAN (so latency - accuracy is higher).
what's the best way to proceed ? so far, I've set up server A as a NTP client to official time servers, and server B as a NTP client to server A. NTP have been running for more than a day, drift file are updated regularly, however I can still see that time is drifting between server A & B (around 1ms every 55 seconds - very regular drift).
any idea / comment ?