[ntp:questions] Linux NTP Kernel unsync flag remains long after NTP & Kernel have PPL sync

Steve Kostecke kostecke at ntp.org
Wed Aug 27 16:50:14 UTC 2008

On 2008-08-27, David L. Mills <mills at udel.edu> wrote:

> David Woolley wrote:
>> David L. Mills wrote:
>>> The bit is never set, so the system calls never show error.
>> That conflicts with the evidence presented by the questioner.  I think 
>> it is true that ntpd never sets it in the kernel(although 4.2.4p4 (which 
>> is more recent than his) does set it in the user space copy.
> The NTP development version on the web (p125) does not set the 
> STA_UNSYNC bit anywhere. A grep for this bit shows only legacy means for 
> ntpdc to clear it. While the production version on the web is dated one 
> day before the development version, its ntp_loopfilter.c file is dated 
> February 2007 and does set it.


> As some of you know, I have been working full time since June 2007 
> cleaning up the code, aligning to the NTPv4 specification, adding new 
> features and rewriting much of the web documentation. The core protocol 
> modules in the production version date from late 2006 and early 2007, so 
> most of the work reported to this list and the hackers list is not in 
> the production version. So, if you suspect I have done something evil 
> and are using the production version, I can't help you.

Both the NTP-stable and NTP-Dev releases are given equal billing on the
NTP Project download page (http://www.ntp.org/downloads.html) and the
NTP Public Services Project download page

All NTP releases are announced in a variety of ways which are detailed
at http://support.ntp.org/bin/view/Main/ReleaseNotifications. We do
not yet offer a dedicated release announcements mailing list but would
consider doing so if there was sufficient interest.

Notifications for every NTP-dev release are sent to the hackers@ mailing
list at the time of the release. These notifications contain change
information as well as download links.

We have made an effort to insure that all releases are well publicized.
But we can't control what version of NTP is shipped with the many OSes
which are out there. Plus, quite a few people prefer to stick with the
software versions which are pre-packaged for and shipped with their
particular OS.

For BSD users FreshPorts currently lists ntp-devel 4.2.5p122
and ntp 4.2.4p4 at http://www.freshports.org/net/ntp-devel/ and
http://www.freshports.org/net/ntp/ respectively.

Debian does not ship any ntp-dev packages so I have set up a build
system for Debian packages of ntp-dev (against the current Debian
stable release "etch" on x86). These packages are available from

If there is sufficient interest "we" could look at leveraging
the openSUSE Build Service, https://build.opensuse.org/, for
building packages for other Linux OSes and architectures. A list
of the supported RPM-based OSes is available about half-way down
I may need assistance from someone well versed in building RPM packages
and setting up RPM archives.

Steve Kostecke <kostecke at ntp.org>
NTP Public Services Project - http://support.ntp.org/

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