Howto monitor ntp server with mrtg

I’m currently maintain several ntp servers that listed in ntppool.org.
Average of all ntp servers listed there, there must be monitoring using mrtg.
After a little searching and asking questions on the mailing list. Here’s my configuration:
———————getntp.pl———————

################################## 
#getntp.pl 
#source : http://www.satsignal.eu/ntp/NTPandMRTG.html 
#budiw 20120728

$ntp_str = `ntpq -c rv $ARGV[0]`;
$val = (split(/\\,/,$ntp_str))[20];
$val =~ s/offset=//i;
$val = int ($val + 100);
if ($val < 0) {
$val = 0;
}
print "0\\n";
print "$val\\n";
print "0\\n";
print "0\\n";

 
—————–ntppackets.pl—————————

#!/usr/bin/perl
use strict;

##################################
#ntppackets.pl
#source from ntp mailing lists
#http://lists.ntp.org/pipermail/pool/2012-July/006049.html

#### Options ####
my $uptimeprog = '/usr/bin/uptime'; # Set to program to give system uptime
my $hostnameprog = '/bin/hostname'; # Set to program to give system hostname

##### Nothing below here should have to be changed #####

# Clear path and get uptime
delete $ENV{PATH};
delete $ENV{BASH_ENV};
my $uptime = `$uptimeprog`;
chomp($uptime);
$uptime=substr($uptime,12);
my $hostname = `$hostnameprog`;
chomp($hostname);

my $received = 0;
my $sent = 0;
my $status = `/usr/bin/ntpdc -c iostats`;
if($status =~ m!received packets:\\s*(-?\\d+)!) {
$received=$1 + 2147483648;
}
if($status =~ m!packets sent:\\s*(-?\\d+)!) {
$sent=$1 + 2147483648;
}

print "$received\\n$sent\n$uptime\\n$hostname\\n";

-----------mrtg.conf---------------------------
#
# NTP Packets
#

Title[ntppackets]: XXX NTP packets
Target[ntppackets]: `/home/budiw/paket/ntp-mrtg/ntppackets.pl`
PageTop[ntppackets]: Received and sent NTP packets for yyy
MaxBytes[ntppackets]: 60000
Options[ntppackets]: growright, nopercent
YLegend[ntppackets]: #/s
ShortLegend[ntppackets]:
Legend1[ntppackets]: Received packets/s
Legend2[ntppackets]: Sent packets/s
Legend3[ntppackets]: Maximal 5 minute received packets/s
Legend4[ntppackets]: Maximal 5 minute sent packets/s
LegendI[ntppackets]:  received packets/s
LegendO[ntppackets]:  sent packets/s
WithPeak[ntppackets]: wmy

#
# NTP offsets
#

Target[xxx_ntp]: `perl /home/budiw/paket/ntp-mrtg/getntp.pl 127.0.0.1`
MaxBytes[xxx_ntp]: 100
MaxBytes2[xxx_ntp]: 200
Unscaled[xxx_ntp]: dwmy
Timezone[xxx_ntp]: GMT+7
Title[xxx_ntp]: NTP statistics for XXX - offset from NTP
Options[xxx_ntp]: integer, gauge, nopercent, growright
YLegend[xxx_ntp]: offset+100 ms
ShortLegend[xxx_ntp]: ms
LegendI[xxx_ntp]:
LegendO[xxx_ntp]: offset:
Legend1[xxx_ntp]: n/a
Legend2[xxx_ntp]: time offset in ms, with 100ms offset added to ensure it's positive!
PageTop[xxx_ntp]: NTP -- XXX

—————–
Here’s one example scripts on action:
NTP – Offsets+100ms

NTP – Received and sent NTP packets for alynne.blankon.in