[ntp:questions] PPS not working on newer kernel/distros

Brandon Applegate brandon at burn.net
Tue Oct 9 17:04:05 UTC 2018

> On Oct 9, 2018, at 5:43 AM, Joachim Fabini <Joachim.Fabini at tuwien.ac.at> wrote:
> Hello Brandon,
> Which version of ntp is deployed on your system?
> Any relevant/suspect output in syslog when restarting ntpd?
> What does ntpq report?
> First guess: please remember http://bugs.ntp.org/show_bug.cgi?id=3367 -
> this was staged (only) for ntp-4.2.8p11. Make sure that either your ntp
> has the patch already or patch your sources manually.
> br Joachim

Hey Joachim,

Actually I think you helped me out a few years ago when I first found this issue.  You gave me a patch which I put against 4.2.8p6 I believe at the time.  I was getting the kcbind error on Ubuntu 14.04.  

So yes, now that I’ve installed 4.2.8p12 (that includes the patch) - I no longer get this error.  The bad news though is that it seems like I never lock on to PPS.  I never get an ‘o’ in my billboard.  If I put fudge flag3 back to 0, I seem to be in business (I get ‘o’ quickly and my offset settles down to near 0).  But (and I don’t have actual before/after graphs or hard data to confirm this) but it seems like it wavers a bit more now than it did previously on Ubuntu 14.04 with fudge flag  3 set to 1.

Nevertheless - I’d still like to understand a bit more about fudge flag 3 on this.  It was working in Ubuntu 14.04, and doesn’t seem to work on Debian 9 (what I settled on now) or Ubuntu 18.04.

I’m not quite sure I understand what the real difference in this flag is ?  Is one mode more accurate than the other ?  Why did it work just fine in an older distro and no longer does ?

Also - thanks for your reply and help on this so far - it’s much appreciated.

Brandon Applegate - CCIE 10273
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