couldn't manage cisco switch interface using Ruby snmp

[Wak Karot]

Hi guy,

I'm just created script to shutdown and bring up cisco switch interface

#!/usr/bin/env ruby
require 'rubygems'
require 'snmp'
include SNMP

manager = Manager.newHost => '10.111.1.30', :WriteCommunity=>
'write', :Version => :SNMPv2c)
varbind = VarBind.new("1.3.6.1.2.1.2.2.1.7.19", Integer(2))
manager.set(varbind)
manager.close

but i got this error

/usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/varbind.rb:562:in
`encode': undefined method `encode' for 2:Fixnum (NoMethodError)
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/varbind.rb:48:in
`encode'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/varbind.rb:47:in
`each'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/varbind.rb:47:in
`encode'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/pdu.rb:181:in
`encode_pdu'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/pdu.rb:204:in
`encode'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/pdu.rb:110:in
`encode'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/manager.rb:478:in
`send_request'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/manager.rb:462:in
`try_request'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/manager.rb:461:in
`times'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/manager.rb:461:in
`try_request'
from /usr/lib/ruby/gems/1.8/gems/snmp-1.0.1/lib/snmp/manager.rb:266:in
`set'
from setsnmp.rb:8

if i using snmpset it worked perfectly, any help