Munin contributed plugins

#!/usr/bin/env ruby

#

# Wildcard-script to monitor network port usage using netstat. To monitor a

# port, link port_<service> to this file. E.g. This plugin shall run by root user

#

#    ln -s /usr/share/munin/node/plugins-auto/port_ /etc/munin/node.d/port_www

#

# ...will monitor www connections. Services are those listed in

# /etc/services. Case service is not listed the numeric value shall be passed

#

# Author: Luis García Acosta

# V 1.0

# Date Tue April 12 09:20:21 CET 2011

require 'rubygems'

require 'munin'

SERVICE   = $0.split('_').last

SERVICE_F = '/etc/services'

PORT      = /^[\d]+(\.[\d]+){0,1}$/ === SERVICE ? SERVICE : %x[grep #{SERVICE} #{SERVICE_F}].split("\t\t")[1].split('/')[0]

class PortMonit < Munin::Plugin

  graph_attributes "#{SERVICE} port usage, known as #{PORT}",

                   :category => 'network',

                   :info => 'This graph shows connection split by the state of the socket.',

                   :vlabel => 'Current connections'

  declare_field :ESTABLISHED,

                :label => 'Established', :draw => :AREA,

                :type => :GAUGE, :min => 0

  declare_field :CLOSE_WAIT,

                :label => 'Waiting close', :draw => :STACK,

                :type => :GAUGE, :min => 0

  declare_field :TIME_WAIT,

                :label => 'Waiting after close', :draw => :STACK,

                :type => :GAUGE, :min => 0

  declare_field :CLOSING,

                :label => 'Closing', :draw => :STACK,

                :type => :GAUGE, :min => 0

  declare_field :LAST_ACK,

                :label => 'Waiting for acknowledgement', :draw => :STACK,

                :type => :GAUGE, :min => 0

  declare_field :FIN_WAIT_1,

                :label => 'Socket closed, connection shutting down', :draw => :STACK,

                :type => :GAUGE, :min => 0

  declare_field :FIN_WAIT_2,

                :label => 'Connection closed, Socket still waiting', :draw => :STACK,

                :type => :GAUGE, :min => 0

  def retrieve_values

    @_netstat = %x[netstat -n -P tcp | egrep "\.#{PORT} "].split("\n")

    { :ESTABLISHED => count(@_netstat, 'ESTABLISHED'),

      :CLOSE_WAIT => count(@_netstat, 'CLOSE_WAIT'),

      :CLOSING => count(@_netstat, 'CLOSING'),

      :LAST_ACK => count(@_netstat, 'LAST_ACK'),

      :FIN_WAIT_1 => count(@_netstat, 'FIN_WAIT_1'),

      :FIN_WAIT_2 => count(@_netstat, 'FIN_WAIT_2'),

      :TIME_WAIT => count(@_netstat, 'TIME_WAIT') }

  end

  private

  def count(source, regex)

    @_result = 0

    source.each { |obj| @_result += 1 if obj.match(regex) }

    return @_result

  end

end

PortMonit.new.run