/usr/share/munin/plugins/uptime is in munin-node 1.4.6-3ubuntu3.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 | #!/bin/sh
# -*- sh -*-
: << =cut
=head1 NAME
uptime - Plugin to measure uptime. 
=head1 NOTES
Especially the average and max values on the bigger graphs (yearly) can be interesting.
=head1 AUTHOR
Contributed by Nicolas Salles
=head1 LICENSE
Unknown license
=head1 MAGIC MARKERS
 #%# family=auto
 #%# capabilities=autoconf
=cut
. $MUNIN_LIBDIR/plugins/plugin.sh
if [ "$1" = "autoconf" ]; then
	echo yes 
	exit 0
fi
if [ "$1" = "config" ]; then
	echo 'graph_title Uptime'
	echo 'graph_args --base 1000 -l 0 '
	echo 'graph_scale no'
	echo 'graph_vlabel uptime in days'
	echo 'graph_category system'
	echo 'uptime.label uptime'
	echo 'uptime.draw AREA'
	print_warning uptime
	print_critical uptime
	exit 0
fi
awk '{printf "uptime.value %.2f\n",$1/86400}' /proc/uptime
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