File: //etc/munin/plugins/open_files
#!/usr/bin/sh
# -*- sh -*-
: << =cut
=head1 NAME
open_files - Plugin to monitor the number of open files in the system
=head1 CONFIGURATION
No configuration
=head1 AUTHOR
Unknown author
=head1 LICENSE
GPLv2
=head1 MAGIC MARKERS
 #%# family=auto
 #%# capabilities=autoconf
=cut
. "$MUNIN_LIBDIR/plugins/plugin.sh"
if [ "$1" = "autoconf" ]; then
	if [ -r /proc/sys/fs/file-nr ]; then
		echo yes
		exit 0
	else
		echo no
		exit 0
	fi
fi
if [ "$1" = "config" ]; then
	echo 'graph_title File table usage'
	echo 'graph_args --base 1000 -l 0'
	echo 'graph_vlabel number of open files'
	echo 'graph_category system'
	echo 'graph_info This graph monitors the Linux open files table.'
	echo 'used.label open files'
	echo 'used.info The number of currently open files.'
	computed_warning=$(awk '{printf "%d", $3*0.92}' < /proc/sys/fs/file-nr)
	computed_critical=$(awk '{printf "%d", $3*0.98}' < /proc/sys/fs/file-nr)
	p_warning=$(print_warning used)
	p_critical=$(print_critical used)
	[ -z "$p_warning" ] && echo "used.warning $computed_warning" || echo "$p_warning"
	[ -z "$p_critical" ] && echo "used.critical $computed_critical" || echo "$p_critical"
	exit 0
fi
awk '{print "used.value " $1-$2}' < /proc/sys/fs/file-nr