[ntp:questions] orphan mode

fealsop fealsop at yahoo.com
Fri May 27 17:43:17 UTC 2011

On May 19, 1:30 pm, Steve Kostecke <koste... at ntp.org> wrote:
> On 2011-05-17, Frank Alsop <feal... at yahoo.com> wrote:
> >    We have a relatively small network and are trying to use ntp
> > peering andorphanmodeand I have a couple of questions.  I have read
> > the info athttp://www.eecis.udel.edu/~mills/ntp/html/orphan.html
> That is the documentation for the current ntp-dev release.
> Please use the documentation shipped with your version of NTP or the
> documentation archived athttp://doc.ntp.org/4.2.4
> > but I am having trouble figuring out the correct "tosorphan" statement we
> > should use.
> > We have a time source at stratum 1.
> > We have 4 "peers" at stratum 2
> > We have multiple nodes at stratum 3
> > We have multiple nodes at stratum 4
> > So, in our ntp.conf file for the 4 stratum 2 "peered" nodes, we have
> > "tosorphan4".  At the website referred to above, we could infer that
> > we need to use "tosorphan5".  What stratum should we use in our
> >orphanstatement?
> 5 is the defaultorphanstratum. Use at least that (i.e. >= 5).
> > Also, we are using 4.2.4p7.  At the following website,
> > you could infer that we need a newer rev of ntp.
> >http://support.ntp.org/bin/view/Support/OrphanMode
> > This page seems to indicate we need at least 4.2.5p101, but at least
> > to me, isn't perfectly clear.
> The current stable release is NTP-4.2.6p3 and you are using NTP-4.2.4p7.
> On the surface it does not look like there's much difference between
> these two versions. But there is; substantial changes were made in the
> 4.2.5* development series.
> Here's how you should be reading these versions:
> NTP-4.2.4p7 == NTP-4 v2.4.7
> NTP-4.2.6p3 == NTP-4 v2.6.3
> If you want to useOrphanModeyou should upgrade to the current stable
> release.
> --
> Steve Kostecke <koste... at ntp.org>
> NTP Public Services Project -http://support.ntp.org/

Thanks, I am recommending to our group to update to ntp 4.2.6p3.
However, I am getting some pushback.  My interpretation of the on-line
material and backed up by your response is that 4.2.4p7 doesn't fully
support orphan mode.  I have seen trouble with ntp synch when we
reboot our system.  We have 4 peers synching to a GPS timesource and
sometimes - rarely - on a reboot, the 4 peers never re-synch.  A
follow up reboot usually fixes it.  However, I don't believe orphan
mode comes into play as long as we have GPS - correct?

Reboots are less reliable if the GPS time source is unavailable.  I
attribute this to the contribution of "tos orphan 4".  I interpret the
on-line documentation taken together with your response to mean that
we have a problem with this "tos orphan 4" statement.  The online
documentation says to set the orphan "greater than any anticipated
stratum that might occur with configured Internet time servers" to
mean that if we, for instance, have servers at stratum 5, we should
set to (at a minimum) "tos orphan 6", and we we have servers at 6,
then set to 7, etc.  However, others interpret the documention to mean
that we only have to set the "tos orphan" to a higher stratum than the
stratum in which we have the "tos orphan 4" statement.  So, the "tos
orphan" statement in our case is at stratum 2, so their opinion is
that we only need to be higher than 2.

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