require 'snmp'
require 'snmp4em'

OID_SYSTEM = "1.3.6.1.2.1.1"
OID_SYSNAME = "1.3.6.1.2.1.1.5.0"
OID_SYSLOCATION = "1.3.6.1.2.1.1.6.0"

EM.run {
  snmp = SNMP4EM::Manager.new(:host => '10.6.57.29')

  request = snmp.bulkwalk(OID_SYSTEM)

  request.callback do |response|
    response[OID_SYSTEM].each do |oid, value|
      puts "#{oid} = #{value}"
    end
  end

  request.errback do |error|
    puts "BULK-WALK got error #{error}"
  end
}