Re: [chrony-users] PPS correction not being applied

[Brian Gieryk <ke6iyc@xxxxxxx>]

This is mine, most online sources are commented out, as internet is
very limited here.

Brian

On Fri, 24 Feb 2017 16:57:15 +0100
Fabian Schörghofer <fabian.schoergi@xxxxxxxxx> wrote:

> What does your chrony.conf look like now?
> 
> I have a similar problem, (also using gpsd and Raspberry Pi with
> GPIO-PPS).
> 
> Am 24.02.2017 16:53, schrieb Brian Gieryk:
> > Bill, PPS is being referenced as GPS now.
> > 
> > Miroslav, that was initial fix.
> > 
> > Now, NMEA offset is +198ms std dev is 7301us
> > 
> > GPS (PPS) is offset +23 us std dev is 19us.
> > 
> > Brian
> > 
> > Sent from my iPhone
> > 
> >> On Feb 24, 2017, at 08:48, Miroslav Lichvar <mlichvar@xxxxxxxxxx>
> >> wrote:
> >>
> >>> On Fri, Feb 24, 2017 at 08:44:02AM -0700, Brian Gieryk wrote:
> >>> Did as suggested, and seems to be working.  NMEA is showing  +/-
> >>> 2599 us and GPS (PPS) is showing +/- 1831 us.
> >>
> >> 1800 microseconds is not that good for a PPS. Usually it's just a
> >> few microseconds, or better. What does the "chronyc sourcestats"
> >> command print?
> >>
> >> -- 
> >> Miroslav Lichvar
> >>
> >> -- 
> >> To unsubscribe email chrony-users-request@xxxxxxxxxxxxxxxxxxxx 
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> >> For help email chrony-users-request@xxxxxxxxxxxxxxxxxxxx 
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> >>
> > 
> 

# This the default chrony.conf file for the Debian chrony package.  After
# editing this file use the command 'invoke-rc.d chrony restart' to make
# your changes take effect.  John Hasler <jhasler@xxxxxxxxxx> 1998-2008

# See www.pool.ntp.org for an explanation of these servers.  Please
# consider joining the project if possible.  If you can't or don't want to
# use these servers I suggest that you try your ISP's nameservers.  We mark
# the servers 'offline' so that chronyd won't try to connect when the link
# is down.  Scripts in /etc/ppp/ip-up.d and /etc/ppp/ip-down.d use chronyc
# commands to switch it on when a dialup link comes up and off when it goes
# down.  Code in /etc/init.d/chrony attempts to determine whether or not
# the link is up at boot time and set the online status accordingly.  If
# you have an always-on connection such as cable omit the 'offline'
# directive and chronyd will default to online.
#
# Note that if Chrony tries to go "online" and dns lookup of the servers
# fails they will be discarded.  Thus under some circumstances it is 
# better to use IP numbers than host names.

#server 0.debian.pool.ntp.org offline minpoll 8
#server 1.debian.pool.ntp.org offline minpoll 8
#server 2.debian.pool.ntp.org offline minpoll 8
#server 3.debian.pool.ntp.org offline minpoll 8


# Look here for the admin password needed for chronyc.  The initial
# password is generated by a random process at install time.  You may
# change it if you wish.

keyfile /etc/chrony/chrony.keys

# Set runtime command key.  Note that if you change the key (not the
# password) to anything other than 1 you will need to edit
# /etc/ppp/ip-up.d/chrony, /etc/ppp/ip-down.d/chrony, /etc/init.d/chrony
# and /etc/cron.weekly/chrony as these scripts use it to get the password.

commandkey 1

# I moved the driftfile to /var/lib/chrony to comply with the Debian
# filesystem standard.

# driftfile /var/lib/chrony/chrony.drift

# Comment this line out to turn off logging.

log tracking measurements statistics refclocks
logdir /var/log/chrony

# Stop bad estimates upsetting machine clock.

maxupdateskew 100.0

# Dump measurements when daemon exits.

dumponexit

# Specify directory for dumping measurements.

dumpdir /var/lib/chrony

# Let computer be a server when it is unsynchronised.

local stratum 10

# Allow computers on the unrouted nets to use the server.

allow 10/8
allow 192.168/16
allow 172.16/12

# This directive forces `chronyd' to send a message to syslog if it
# makes a system clock adjustment larger than a threshold value in seconds.

logchange 0.5

# This directive defines an email address to which mail should be sent
# if chronyd applies a correction exceeding a particular threshold to the
# system clock.


# mailonchange root@localhost 0.5

# This directive tells chrony to regulate the real-time clock and tells it
# Where to store related data.  It may not work on some newer motherboards
# that use the HPET real-time clock.  It requires enhanced real-time
# support in the kernel.  I've commented it out because with certain
# combinations of motherboard and kernel it is reported to cause lockups.

# rtcfile /var/lib/chrony/chrony.rtc

# If the last line of this file reads 'rtconutc' chrony will assume that
# the CMOS clock is on UTC (GMT).  If it reads '# rtconutc' or is absent
# chrony will assume local time.  The line (if any) was written by the
# chrony postinst based on what it found in /etc/default/rcS.  You may
# change it if necessary. 
# rtconutc

server time.nist.gov offline minpoll 8
# server 1.us.pool.ntp.org offline minpoll 8
# server 2.us.pool.ntp.org offline minpoll 8
# server 3.us.pool.ntp.org offline minpoll 8

driftfile /var/lib/chrony/drift

allow

# set larger delay to allow the NMEA source to overlap with
# the other sources to avoid falseticker status

# offline sources

refclock SHM 0 refid NMEA noselect
refclock PPS /dev/pps0 lock NMEA refid GPS