"Weiner, Michael" <weinerm@xxxxxxx> writes: > What I am trying to do actually is build an authoritative or > reference time server that we can use here for testing daylight > saving time adjustments in our environment. Using ntp to test future daylight savings time transitions seems like an awfully round-about way to do it. First of all, ntp tries really hard (too hard if you ask me) to never set a bad time. All your clients under test would have to be tested by restarting ntpd with the -g option every time you wanted to jump the time back to before the transition. If you are going to go to all that trouble, you might as well not run ntpd and just type "date <time-and-date>" and reset the time by hand. The other problem is that the stock Linux kernel doesn't talk to reference clocks. It needs some patches to do the PPS (Pulse Per Second) protocol that reference clocks use to indicate the precise top of the second. (As someone else mentioned, you can still use the phony "local" refclock to have your server pretend it still has a valid time. In that case just set the time on your server to be the time under test, restart ntpd and then restart the ntpd's on the clients under test remembering to use the "-g" flag.) Q: anyone know why the PPS patches never seem to make it into the real kernel sources? -wolfgang -- Wolfgang S. Rupprecht http://www.wsrcc.com/wolfgang/