diff --git a/Makefile b/Makefile
index f5c3d00..3907b7b 100644
--- a/Makefile
+++ b/Makefile
@@ -52,7 +52,7 @@ show-roots:
 
 show-time:
 	-@$(CHRONY_STATUS) && $(CHRONY_STATS)
-	-@watch -d -n 2 "$(CHRONY_STATUS) && echo "--" && $(CHRONY_STATS) && echo "--" && $(CHRONY_STATS_SOURCES)"
+	-@watch -d -n 2 "$(CHRONY_STATUS) && echo "-- Statistiques générales :" && $(CHRONY_STATS) && echo "-- Statistiques sur les sources :" && $(CHRONY_STATS_SOURCES) && echo "-- Statistiques sur les clients :" && chronyc clients"
 
 store-repair:
 	$(TIME) nix-store --verify --check-contents --repair
diff --git a/services/monitoring-munin.nix b/services/monitoring-munin.nix
index ebde24e..6591a85 100644
--- a/services/monitoring-munin.nix
+++ b/services/monitoring-munin.nix
@@ -30,6 +30,14 @@ mkIf flags.munin {
       ignore_file ^sensors_-wrapped$
       ignore_file ^.sensors_-wrapped$
     '';
+    extraPlugins = {
+      chrony = /etc/nixos/base/services/munin-chrony;
+      chrony_tracking_stratum = /etc/nixos/base/services/munin-chrony-tracking-stratum;
+      chrony_tracking_ppm = /etc/nixos/base/services/munin-chrony-tracking-ppm;
+      chrony_tracking_time_ = /etc/nixos/base/services/munin-chrony-tracking-time;
+      chrony_tracking_time_root = /etc/nixos/base/services/munin-chrony-tracking-time-root;
+      chrony_tracking_update_time = /etc/nixos/base/services/munin-chrony-tracking-update-time;
+    };
   };
   systemd.services.munin-node = {
     path = with pkgs; [ munin lm_sensors ];
diff --git a/services/munin-chrony b/services/munin-chrony
new file mode 100755
index 0000000..811b7ec
--- /dev/null
+++ b/services/munin-chrony
@@ -0,0 +1,123 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+parse Chrony Tracking output for timeserver status information
+
+=head1 APPLICABLE SYSTEMS
+
+Any system with a local chronyd service.
+
+=head1 CONFIGURATION
+
+No configuration.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+Revision 0.1 2008/08/23 13:06:00 joti
+
+  First version only chronyc tracking, autodetection included.
+
+Revision 0.2 2008/10/11 16:09:00 joti
+
+  Added scaling of other values to match with frequency, added more description to fields
+
+Revision 0.3 2014/02/16 zjttoefs
+
+  reduce forking by using awk
+  do not limit output precision
+  add stratum monitoring
+  detect slow/fast time or freqency and adjust sign of value accordingly
+  remove commented out code
+
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
+=head1 AUTHOR
+
+  joti
+  zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
+
+=cut
+
+CHRONYC="$(which chronyc | head -1)"
+
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="stratum		1	^Stratum		Stratum
+	systime		1000000	^System.time		System Time (us)
+	offsetlast	1000000	^Last.offset		Last Offset (us)
+	offsetrms	1000000	^RMS.offset		RMS Offset (us)
+	frequency	1	^Frequency		Frequency (ppm)
+	residualfreq	1	^Residual.freq		Residual Freq (ppm)
+	skew		1	^Skew			Skew (ppm)
+	rootdelay	1000000	^Root.delay		Root Delay (us)
+	rootdispersion	1000000	^Root.dispersion	Root Dispersion (us)
+	updateinterval	1	^Update.interval	Update Interval (s)"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
+
+if [ "$1" = "autoconf" ]; then
+	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
+		echo yes
+	else
+		echo "no (missing 'chronyc' executable)"
+	fi
+	exit 0
+fi
+
+if [ "$1" = "config" ]; then
+	echo 'graph_title Chrony Tracking Stats'
+	echo 'graph_args --base 1000 -l 0'
+	echo 'graph_vlabel (time,ppm)'
+	echo 'graph_category time'
+	echo 'graph_scale no'
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
+	exit 0
+fi
+
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done
diff --git a/services/munin-chrony-tracking-ppm b/services/munin-chrony-tracking-ppm
new file mode 100755
index 0000000..da1d022
--- /dev/null
+++ b/services/munin-chrony-tracking-ppm
@@ -0,0 +1,116 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+parse Chrony Tracking output for timeserver status information
+
+=head1 APPLICABLE SYSTEMS
+
+Any system with a local chronyd service.
+
+=head1 CONFIGURATION
+
+No configuration.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+Revision 0.1 2008/08/23 13:06:00 joti
+
+  First version only chronyc tracking, autodetection included.
+
+Revision 0.2 2008/10/11 16:09:00 joti
+
+  Added scaling of other values to match with frequency, added more description to fields
+
+Revision 0.3 2014/02/16 zjttoefs
+
+  reduce forking by using awk
+  do not limit output precision
+  add stratum monitoring
+  detect slow/fast time or freqency and adjust sign of value accordingly
+  remove commented out code
+
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
+=head1 AUTHOR
+
+  joti
+  zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
+
+=cut
+
+CHRONYC="$(which chronyc | head -1)"
+
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="frequency	1	^Frequency		Local Clock Frequency Drift (ppm)
+	residualfreq	1	^Residual.freq		Residual Freq (ppm)
+	skew		1	^Skew			Skew (ppm)"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
+
+if [ "$1" = "autoconf" ]; then
+	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
+		echo yes
+	else
+		echo "no (missing 'chronyc' executable)"
+	fi
+	exit 0
+fi
+
+if [ "$1" = "config" ]; then
+	echo 'graph_title Chrony Tracking Stats - Frequencies stability'
+	echo 'graph_args --base 1000 -l 0'
+	echo 'graph_vlabel (ppm)'
+	echo 'graph_category time'
+	echo 'graph_scale no'
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
+	exit 0
+fi
+
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done
diff --git a/services/munin-chrony-tracking-stratum b/services/munin-chrony-tracking-stratum
new file mode 100755
index 0000000..bf25239
--- /dev/null
+++ b/services/munin-chrony-tracking-stratum
@@ -0,0 +1,116 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+parse Chrony Tracking output for timeserver status information
+
+=head1 APPLICABLE SYSTEMS
+
+Any system with a local chronyd service.
+
+=head1 CONFIGURATION
+
+No configuration.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+Revision 0.1 2008/08/23 13:06:00 joti
+
+  First version only chronyc tracking, autodetection included.
+
+Revision 0.2 2008/10/11 16:09:00 joti
+
+  Added scaling of other values to match with frequency, added more description to fields
+
+Revision 0.3 2014/02/16 zjttoefs
+
+  reduce forking by using awk
+  do not limit output precision
+  add stratum monitoring
+  detect slow/fast time or freqency and adjust sign of value accordingly
+  remove commented out code
+
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
+=head1 AUTHOR
+
+  joti
+  zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
+
+=cut
+
+CHRONYC="$(which chronyc | head -1)"
+
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="stratum		1	^Stratum		Stratum"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
+
+if [ "$1" = "autoconf" ]; then
+	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
+		echo yes
+	else
+		echo "no (missing 'chronyc' executable)"
+	fi
+	exit 0
+fi
+
+if [ "$1" = "config" ]; then
+	echo 'graph_title Chrony Tracking Stats - Stratum'
+	echo 'graph_args --base 1000 -l 0'
+	echo 'graph_vlabel (stratum)'
+	echo 'graph_category time'
+	echo 'graph_scale no'
+	echo 'stratum.warning 8'
+	echo 'stratum.critical 11'
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
+	exit 0
+fi
+
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done
diff --git a/services/munin-chrony-tracking-time b/services/munin-chrony-tracking-time
new file mode 100755
index 0000000..cae65ee
--- /dev/null
+++ b/services/munin-chrony-tracking-time
@@ -0,0 +1,118 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+parse Chrony Tracking output for timeserver status information
+
+=head1 APPLICABLE SYSTEMS
+
+Any system with a local chronyd service.
+
+=head1 CONFIGURATION
+
+No configuration.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+Revision 0.1 2008/08/23 13:06:00 joti
+
+  First version only chronyc tracking, autodetection included.
+
+Revision 0.2 2008/10/11 16:09:00 joti
+
+  Added scaling of other values to match with frequency, added more description to fields
+
+Revision 0.3 2014/02/16 zjttoefs
+
+  reduce forking by using awk
+  do not limit output precision
+  add stratum monitoring
+  detect slow/fast time or freqency and adjust sign of value accordingly
+  remove commented out code
+
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
+=head1 AUTHOR
+
+  joti
+  zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
+
+=cut
+
+CHRONYC="$(which chronyc | head -1)"
+
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="systime		1000000	^System.time		System Time (us)
+	offsetlast	1000000	^Last.offset		Last Offset (us)
+	offsetrms	1000000	^RMS.offset		RMS Offset (us)
+	rootdelay	1000000	^Root.delay		Root Delay (us)
+	rootdispersion	1000000	^Root.dispersion	Root Dispersion (us)"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
+
+if [ "$1" = "autoconf" ]; then
+	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
+		echo yes
+	else
+		echo "no (missing 'chronyc' executable)"
+	fi
+	exit 0
+fi
+
+if [ "$1" = "config" ]; then
+	echo 'graph_title Chrony Tracking Stats - Time'
+	echo 'graph_args --base 1000 -l 0'
+	echo 'graph_vlabel (time)'
+	echo 'graph_category time'
+	echo 'graph_scale no'
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
+	exit 0
+fi
+
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done
diff --git a/services/munin-chrony-tracking-time-root b/services/munin-chrony-tracking-time-root
new file mode 100644
index 0000000..fa898fc
--- /dev/null
+++ b/services/munin-chrony-tracking-time-root
@@ -0,0 +1,115 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+parse Chrony Tracking output for timeserver status information
+
+=head1 APPLICABLE SYSTEMS
+
+Any system with a local chronyd service.
+
+=head1 CONFIGURATION
+
+No configuration.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+Revision 0.1 2008/08/23 13:06:00 joti
+
+  First version only chronyc tracking, autodetection included.
+
+Revision 0.2 2008/10/11 16:09:00 joti
+
+  Added scaling of other values to match with frequency, added more description to fields
+
+Revision 0.3 2014/02/16 zjttoefs
+
+  reduce forking by using awk
+  do not limit output precision
+  add stratum monitoring
+  detect slow/fast time or freqency and adjust sign of value accordingly
+  remove commented out code
+
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
+=head1 AUTHOR
+
+  joti
+  zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
+
+=cut
+
+CHRONYC="$(which chronyc | head -1)"
+
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="rootdelay	1000000	^Root.delay		Root Delay (us)
+	rootdispersion	1000000	^Root.dispersion	Root Dispersion (us)"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
+
+if [ "$1" = "autoconf" ]; then
+	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
+		echo yes
+	else
+		echo "no (missing 'chronyc' executable)"
+	fi
+	exit 0
+fi
+
+if [ "$1" = "config" ]; then
+	echo 'graph_title Chrony Tracking Stats - Root Time'
+	echo 'graph_args --base 1000 -l 0'
+	echo 'graph_vlabel (time)'
+	echo 'graph_category time'
+	echo 'graph_scale no'
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
+	exit 0
+fi
+
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done
diff --git a/services/munin-chrony-tracking-update-time b/services/munin-chrony-tracking-update-time
new file mode 100755
index 0000000..1136b04
--- /dev/null
+++ b/services/munin-chrony-tracking-update-time
@@ -0,0 +1,114 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+parse Chrony Tracking output for timeserver status information
+
+=head1 APPLICABLE SYSTEMS
+
+Any system with a local chronyd service.
+
+=head1 CONFIGURATION
+
+No configuration.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+Revision 0.1 2008/08/23 13:06:00 joti
+
+  First version only chronyc tracking, autodetection included.
+
+Revision 0.2 2008/10/11 16:09:00 joti
+
+  Added scaling of other values to match with frequency, added more description to fields
+
+Revision 0.3 2014/02/16 zjttoefs
+
+  reduce forking by using awk
+  do not limit output precision
+  add stratum monitoring
+  detect slow/fast time or freqency and adjust sign of value accordingly
+  remove commented out code
+
+Revision 0.4 2016/11/10 Lars Kruse
+
+  rewrite field handling
+  use "which" for "chronyc" location
+  switch from "bash" to "sh"
+  fix exit code of failing "autoconf"
+
+=head1 AUTHOR
+
+  joti
+  zjttoefs
+  Lars Kruse <devel@sumpfralle.de>
+
+=cut
+
+CHRONYC="$(which chronyc | head -1)"
+
+# Frequency has extremely higher values than other. Therefore they are fitted by scaling via suitable factors.
+# field definitions:
+#   - munin fieldname
+#   - factor for graph visualization (all values are supposed to reach a similar dimension)
+#   - regular expression of the chrony output line (may not contain whitespace, case insensitive)
+#   - label (may include "%d" for including the factor; may contain whitespace)
+fields="updateinterval	1	^Update.interval	Update Interval (s)"
+
+# chrony example output (v2.4.1):
+#   Reference ID    : 131.188.3.221 (ntp1.rrze.uni-erlangen.de)
+#   Stratum         : 2
+#   Ref time (UTC)  : Thu Nov 10 22:39:50 2016
+#   System time     : 0.000503798 seconds slow of NTP time
+#   Last offset     : +0.000254355 seconds
+#   RMS offset      : 0.002186779 seconds
+#   Frequency       : 17.716 ppm slow
+#   Residual freq   : +0.066 ppm
+#   Skew            : 4.035 ppm
+#   Root delay      : 0.042980 seconds
+#   Root dispersion : 0.005391 seconds
+#   Update interval : 258.4 seconds
+#   Leap status     : Normal
+
+
+if [ "$1" = "autoconf" ]; then
+	if [ -n "$CHRONYC" ] && [ -x "$CHRONYC" ]; then
+		echo yes
+	else
+		echo "no (missing 'chronyc' executable)"
+	fi
+	exit 0
+fi
+
+if [ "$1" = "config" ]; then
+	echo 'graph_title Chrony Tracking Stats - Update interval'
+	echo 'graph_args --base 1000 -l 0'
+	echo 'graph_vlabel (time)'
+	echo 'graph_category time'
+	echo 'graph_scale no'
+	echo "$fields" | while read fieldname factor regex label; do
+		# insert the factor, if "%d" is part of the label
+		printf "${fieldname}.label $label\n" "$factor"
+		echo "${fieldname}.type GAUGE"
+	done
+	exit 0
+fi
+
+chrony_status="$("$CHRONYC" tracking)"
+echo "$fields" | while read fieldname factor regex label; do
+	status_line="$(echo "$chrony_status" | grep -i -- "$regex " | cut -d ":" -f 2-)"
+	if [ -z "$status_line" ]; then
+		value="U"
+	else
+		# the keyword "slow" indicates negative values
+		value="$(echo "$status_line" | awk '{ /slow/ ? SIGN=-1 : SIGN=1; print $1 * SIGN * '"$factor"' }')"
+	fi
+	echo "${fieldname}.value $value"
+done