    # File lib/fog/xenserver/requests/compute/create_vbd.rb, line 7
            def create_vbd( vm_ref, vdi_ref, config = {} )
              raise ArgumentError.new('Invalid config') if config.nil?
              vm_ref = vm_ref.reference if vm_ref.kind_of? Fog::Compute::XenServer::Server
              vdi_ref = vdi_ref.reference if vdi_ref.kind_of? Fog::Compute::XenServer::VDI
              config.reject! { |k,v| (k == :server) or (k == :vdi) }
              default_config = {
                :VM => vm_ref,
                :VDI => vdi_ref,
                :empty => false,
                :other_config => {'owner' => ''},
                :userdevice => "0",
                :bootable => true,
                :mode => 'RW',
                :qos_algorithm_type=> '',
                :qos_algorithm_params=> {},
                :qos_supported_algorithms=> [],
                :type => 'Disk'
              }.merge config

              @connection.request({:parser => Fog::Parsers::XenServer::Base.new, :method => 'VBD.create'}, default_config )
            end