Munin contributed plugins

#!/usr/bin/env ruby

"

=head1 NAME

snmp__linksys_poe - Munin plugin to monitor the current supplied by Linksys PoE

switches.

Requires ruby and the ruby SNMP library.

=head1 APPLICABLE SYSTEMS

I wrote this to query SRW2008MP switches and determined the OIDs by trial and

error.  There may be other Linksys devices that this will also work for.

=head1 CONFIGURATION

This plugin defaults to SNMP version 2c and a community string of 'public'.  The

defaults can be overridden in the usual way:

    [snmp_*]

        env.version 1

        env.community private

SNMP version 3 is not supported.

=head1 INTERPRETATION

The plugin simply reports the current being supplied on each of the device's

PoE ports.

=head1 MIB INFORMATION

Information is gathered from Linksys' private MIB space, so it's probably only

applicable to Linksys devices.  I have been unable to get an actual copy of

the appropriate MIB, so I don't know the actual names of the values I'm

retrieving.

=head1 MAGIC MARKERS

  #%# family=snmpauto contrib

  #%# capabilities=snmpconf

=head1 VERSION

  1.0

=head1 BUGS

None known.

=head1 AUTHOR

Written by Phil Gold <phil_g@pobox.com>.

=head1 LICENSE

CC0 <http://creativecommons.org/publicdomain/zero/1.0/>

To the extent possible under law, all copyright and related or neighboring

rights to this plugin are waived.  Do with it as you wish.

=cut

"

require 'snmp'

idx_oid = 'enterprises.3955.89.108.1.1.2'

max_oid = 'enterprises.3955.89.108.1.1.6'

cur_oid = 'enterprises.3955.89.108.1.1.5'

community = ENV['community'] || 'public'

version = ENV['version'] == '1' ? :SNMPv1 : :SNMPv2c

case ARGV[0]

when 'snmpconf'

  puts 'require 1.3.6.1.4.1.3955.89.108.1.1.2.1. [0-9]'

  puts 'require 1.3.6.1.4.1.3955.89.108.1.1.5.1. [0-9]'

  puts 'require 1.3.6.1.4.1.3955.89.108.1.1.6.1. [0-9]'

  exit 0

when 'config'

  host = $0.match('^(?:|.*\/)snmp_([^_]+)')[1]

  puts "host_name #{host}"

  puts 'graph_title PoE Power Usage'

  puts 'graph_vlabel Watts'

  puts 'graph_category sensors'

  max_current = 0

  SNMP::Manager.open(Host: host,

                     Community: community,

                     Version: version) do |manager|

    manager.walk([idx_oid, max_oid]) do |row|

      puts "iface_#{row[0].value}.label Port #{row[0].value}"

      puts "iface_#{row[0].value}.cdef iface_#{row[0].value},1000,/"

      puts "iface_#{row[0].value}.line #{row[1].value.to_f / 1000}"

      max_current = row[1].value if row[1].value > max_current

    end

  end

  puts "graph_args --upper-limit #{max_current.to_f / 1000}"

  exit 0

else

  host = $0.match('^(?:|.*\/)snmp_([^_]+)')[1]

  SNMP::Manager.open(Host: host,

                     Community: community,

                     Version: version) do |manager|

    manager.walk([idx_oid, cur_oid]) do |row|

      puts "iface_#{row[0].value}.value #{row[1].value}"

    end

  end

end