In article <[EMAIL PROTECTED]>, David Andersen <[EMAIL PROTECTED]> writes >You'll get more than you expect -- the offset you're observing on >ADSL is very likely wrong, because the delays your packets experience >on adsl aren't symmetric. NTP assumes symmetry. So I wouldn't >actually believe that a 1ms offset is really 1ms off, depending on >the RTT to your ISP.
Yes, I knew about that, but all I can go by as a newbie is what MRTG is telling me - and it's telling me that my time offsets are too big... > >But there actually are ways to mitigate the offset spikes. You might >be able, for instance, to configure your gateway to prioritize NTP >packets over everything else, which will help with half of the >problem. You won't be able to do the same at your ISP, of course, so >it's not a perfect solution. A Netgear DG814 is too brain-dead to understand QoS. One thing at a time... > >Installing a local GPS-synched server is the right answer if you >really care. And it's fun. :) The Soekris boxes rock. I assume >you've already seen Poul-Henning Kamp's page about using his net4801 >with FreeBSD to act as a high precision timeserver? If you want sub- >microsecond, you'll probably have to replace the oscillator on the 4801. Yes, I've read his page on that - as an electronic engineer, I even understood it! That will be the next stage - I'll settle for units of microseconds for the moment. > >And - most OSes should do the trick. FreeBSD has a really nice >precision timekeeping interface, though -- and it makes a marvelously >solid time server. I'm running it on a few Net4801s and recommend >it. You can very easily build an image for it using another bit of >phk's magic called 'nanobsd' (it's in the source tree). As I just asked John A. - is it in the default kernel? Thanks for your comments, -- Geoff Powell _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
