# Welcome to the chrony configuration file. See chrony.conf(5) for more
# information about usable directives.

# Use Debian vendor zone.
#pool 2.debian.pool.ntp.org iburst

# Use time sources from DHCP.
sourcedir /run/chrony-dhcp

# Use NTP sources found in /etc/chrony/sources.d.
sourcedir /etc/chrony/sources.d

# This directive specifies the location of the file containing ID/key pairs for
# NTP authentication.
keyfile /etc/chrony/chrony.keys

# This directive specifies the file into which chronyd will store the rate
# information.
driftfile /var/lib/chrony/chrony.drift

# Save NTS keys and cookies.
ntsdumpdir /var/lib/chrony

# Uncomment the following line to turn logging on.
#log tracking measurements statistics

# Log files location.
logdir /var/log/chrony

# Stop bad estimates upsetting machine clock.
maxupdateskew 100.0

# This directive enables kernel synchronisation (every 11 minutes) of the
# real-time clock. Note that it can't be used along with the 'rtcfile' directive.
rtcsync

# Step the system clock instead of slewing it if the adjustment is larger than
# one second, but only in the first three clock updates.
makestep 1 3

# Get TAI-UTC offset and leap seconds from the system tz database.
# This directive must be commented out when using time sources serving
# leap-smeared time.
leapseclist /usr/share/zoneinfo/leap-seconds.list

# Include configuration files found in /etc/chrony/conf.d.
#confdir /etc/chrony/conf.d


# ACL
# I have set it to RFC1918 because I'm using my firewall to explicitly allow access to NTP server
allow 192.168.0.0/16
allow 10.0.0.0/8
allow 172.16.0.0/12

# Explicitly tell clients that we are stratum 1
local stratum 1


# Onboard GPS clock

#refclock SHM 0 refid NMEA offset 0.000 precision 1e-3 poll 3 noselect
refclock SHM 0 refid NMEA offset 0.125 precision 1e-3 poll 3 noselect
refclock PPS /dev/pps0 refid PPS lock NMEA poll 3