From ba5030ffce428d16b2004893555a18c1176221a7 Mon Sep 17 00:00:00 2001 From: ohrensessel Date: Tue, 1 Jul 2014 17:49:35 +0200 Subject: [PATCH] Add munin plugin to monitor dhcp leases --- files/usr/share/munin/plugins/dhcp-pool | 192 ++++++++++++++++++++++++ manifests/sysadmin.pp | 12 ++ 2 files changed, 204 insertions(+) create mode 100644 files/usr/share/munin/plugins/dhcp-pool diff --git a/files/usr/share/munin/plugins/dhcp-pool b/files/usr/share/munin/plugins/dhcp-pool new file mode 100644 index 0000000..2cb715d --- /dev/null +++ b/files/usr/share/munin/plugins/dhcp-pool @@ -0,0 +1,192 @@ +#!/usr/bin/perl -w +# +# Copyright (C) 2008 Rien Broekstra +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License +# as published by the Free Software Foundation; version 2 dated June, +# 1991. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +# +# +# Munin plugin to measure saturation of DHCP pools. +# +# Configuration variables: +# +# conffile - path to dhcpd's configuration file (default "/etc/dhcpd.conf") +# leasefile - path to dhcpd's leases file (default "/var/lib/dhcp/dhcpd.leases") +# +# Parameters: +# +# config (required) +# +# Version 1.0, 2-12-2008 + +use POSIX; +use Time::Local; +use strict; + +my $CONFFILE = exists $ENV{'conffile'} ? $ENV{'conffile'} : "/etc/dhcpd.conf"; +my $LEASEFILE = exists $ENV{'leasefile'} ? $ENV{'leasefile'} : "/var/lib/dhcp/dhcpd.leases"; + +if ( defined $ARGV[0] and $ARGV[0] eq "autoconf" ) { + +} +elsif ( defined $ARGV[0] and $ARGV[0] eq "config" ) { + my (%pools, $start, $label); + + # Print general information + print "graph_title DHCP pool usage (in %)\n"; + print "graph_args --upper-limit 100 -l 0\n"; + print "graph_vlabel %\n"; + print "graph_category network\n"; + + # Determine the available IP pools + %pools = determine_pools(); + + # Print a label for each pool + foreach $start (keys %pools) { + $label = ip2string($start); + $label =~ s/\./\_/g; + print "$label.label Pool ".ip2string($start)."\n"; + print "$label.warning 75\n"; + print "$label.critical 100\n"; + } +} +else { + my (@activeleases, %pools, $start, $end, $size, $free, $label, $lease); + + # Determine all leased IP addresses + @activeleases = determine_active_leases(); + + # Determine the available IP pools + %pools = determine_pools(); + + # For each pool, count how many leases from that pool are currently active + foreach $start (keys %pools) { + $size = $pools{$start}; + $end = $start+$size; + $free = $size; + + foreach $lease (@activeleases) { + if ($lease >= $start && $lease <= $end) { + $free--; + } + } + $label = ip2string($start); + $label =~ s/\./\_/g; + print "$label.value ".sprintf("%.1f", 100*($size-$free)/$size)."\n"; + } +} + +# Parse dhcpd.conf for range statements. +# +# Returns a hash with start IP -> size +sub determine_pools { + my (%pools, @conffile, $line, $start, $end, $size); + + open(CONFFILE, "<${CONFFILE}") || exit -1; + @conffile = ; + close (CONFFILE); + + foreach $line (@conffile) { + if ($line =~ /range[\s]+([\d]+\.[\d]+\.[\d]+\.[\d]+)[\s]+([\d]+\.[\d]+\.[\d]+\.[\d]+)/) { + $start = string2ip($1); + $end = string2ip($2); + $size = $end - $start; + defined($start) || next; + defined($end) || next; + + $pools{$start} = $size; + } + } + return %pools; +} + +# Very simple parser for dhcpd.leases. This will break very easily if dhcpd decides to +# format the file differently. Ideally a simple recursive-descent parser should be used. +# +# Returns an array with currently leased IP's +sub determine_active_leases { + my (@leasefile, $startdate, $enddate, $lease, @activeleases, $mytz, $line, %saw); + + open(LEASEFILE, "<${LEASEFILE}") || exit -1; + @leasefile = ; + close (LEASEFILE); + + @activeleases = (); + + # Portable way of converting a GMT date/time string to timestamp is setting TZ to UTC, and then calling mktime() + $mytz = $ENV{'TZ'}; + $ENV{'TZ'} = 'UTC 0'; + tzset(); + + foreach $line (@leasefile) { + if ($line =~ /lease ([\d]+\.[\d]+\.[\d]+\.[\d]+)/) { + $lease = string2ip($1); + defined($lease) || next; + + undef $startdate; + undef $enddate; + } + elsif ($line =~ /starts \d ([\d]{4})\/([\d]{2})\/([\d]{2}) ([\d]{2}):([\d]{2}):([\d]{2})/) { + $startdate = mktime($6, $5, $4, $3, $2-1, $1-1900, 0, 0); + } + elsif ($line =~ /ends \d ([\d]{4})\/([\d]{2})\/([\d]{2}) ([\d]{2}):([\d]{2}):([\d]{2})/) { + $enddate = mktime($6, $5, $4, $3, $2-1, $1-1900, 0, 0); + if (defined($enddate) && defined($startdate) && defined($lease)) { + if ($startdate < time() && $enddate > time()) { + push (@activeleases, $lease); + } + } + } + + } + + # Set TZ back to its original setting + if (defined($mytz)) { + $ENV{'TZ'} = $mytz; + } + else { + delete $ENV{'TZ'}; + } + tzset(); + + # Sort the array, strip doubles, and return + return grep(!$saw{$_}++, @activeleases); +} + +# +# Helper routine to convert an IP address a.b.c.d into an integer +# +# Returns an integer representation of an IP address +sub string2ip { + my $string = shift; + defined($string) || return undef; + if ($string =~ /([\d]+)\.([\d]+)\.([\d]+)\.([\d]+)/) { + if ($1 < 0 || $1 > 255 || $2 < 0 || $2 > 255 || $3 < 0 || $3 > 255 || $4 < 0 || $4 > 255) { + return undef; + } + else { + return $1 << 24 | $2 << 16 | $3 << 8 | $4; + } + } + return undef; +} + +# +# Returns a dotted quad notation of an +# +sub ip2string { + my $ip = shift; + defined ($ip) || return undef; + return sprintf ("%d.%d.%d.%d", ($ip >> 24) & 0xff, ($ip >> 16) & 0xff, ($ip >> 8) & 0xff, $ip & 0xff); +} diff --git a/manifests/sysadmin.pp b/manifests/sysadmin.pp index 4dab594..a6586b9 100644 --- a/manifests/sysadmin.pp +++ b/manifests/sysadmin.pp @@ -162,6 +162,18 @@ host <%= @ipaddress_eth0 %> '/etc/munin/plugins/udp-statistics': ensure => link, target => '/usr/share/munin/plugins/udp-statistics'; + '/usr/share/munin/plugins/dhcp-pool': + ensure => file, + mode => '0755', + source => 'puppet:///modules/ff_gw/usr/share/munin/plugins/dhcp-pool'; + '/etc/munin/plugins/dhcp-pool': + ensure => link, + target => '/usr/share/munin/plugins/dhcp-pool'; + '/etc/munin/plugin-conf.d/dhcp-pool': + ensure => file, + content => '[dhcp-pool] +env.leasefile /var/lib/dhcp/dhcpd.leases +env.conffile /etc/dhcp/dhcpd.conf'; '/etc/munin/plugins/if_mullvad': ensure => link, target => '/usr/share/munin/plugins/if_';