On Tue, Mar 3, 2009 at 7:21 PM, Jason <[email protected]> wrote: > I'm pretty sure the appliance might be more capable than the LVC18, same > manufacturer as many gov't agencies use, better antenna, highest grade > coaxial cable from the antennas, etc. Has PPS and 10Mhz outputs. The > problem is getting the PPS into the servers.
One thing you could experiment with is doing a sort of "poor man's PPS" over Ethernet using broadcast NTP mode with the GPS devices as servers and as short a poll interval as is possible. If all of the blades are running the same hardware, kernel, and NTP versions, using broadcast mode would result in NTP clients having essentially the same timing information, and so they should behave as similarly as possible within the limits of the hardware and environment. Ntpd would still have to deal with the non-deterministic load and thermal variations on each blade, of course, but such a scheme might help with your goal of keeping all the blades as closely synced as possible to each other. Obviously to address failure you would need three or more GPS devices putting out broadcast packets in each broadcast domain, using the prefer keyword on the clients to select one as the leader of the pack. Anyway, this is just an idea I had in the shower this morning. I am sure the actual ntpd developers here will point out many reasons why my scheme is not workable. However, it sounds as though you have the resources to fully experiment with this - or any other proposed solution - in a duplicate hardware environment, correct? -- RPM _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
