Transport tweaks
****************


TRAP over multiple transports
=============================

The following script sends two SNMP TRAP notification using the
following options:

* with SNMPv1

* with community name 'public'

* over IPv4/UDP and IPv6/UDP

* send TRAP notification

* to a Manager at demo.snmplabs.com:162 and [::1]

* with TRAP ID 'coldStart' specified as an OID

* include managed objects information:

* with default Uptime value

* with default Agent Address with '127.0.0.1'

* overriding Enterprise OID with 1.3.6.1.4.1.20408.4.1.1.2

The following Net-SNMP commands will produce similar SNMP
notification:

   $ snmptrap -v1 -c public udp:demo.snmplabs.com 1.3.6.1.4.1.20408.4.1.1.2 127.0.0.1 1 0 12345
   $ snmptrap -v1 -c public udp6:[::1] 1.3.6.1.4.1.20408.4.1.1.2 127.0.0.1 1 0 12345

   from pysnmp.carrier.asyncore.dispatch import AsyncoreDispatcher
   from pysnmp.carrier.asyncore.dgram import udp, udp6, unix
   from pyasn1.codec.ber import encoder
   from pysnmp.proto import api

   # Protocol version to use
   pMod = api.protoModules[api.protoVersion1]
   # pMod = api.protoModules[api.protoVersion2c]

   # Build PDU
   trapPDU = pMod.TrapPDU()
   pMod.apiTrapPDU.setDefaults(trapPDU)

   # Traps have quite different semantics across proto versions
   if pMod == api.protoModules[api.protoVersion1]:
       pMod.apiTrapPDU.setEnterprise(trapPDU, (1, 3, 6, 1, 1, 2, 3, 4, 1))
       pMod.apiTrapPDU.setGenericTrap(trapPDU, 'coldStart')

   # Build message
   trapMsg = pMod.Message()
   pMod.apiMessage.setDefaults(trapMsg)
   pMod.apiMessage.setCommunity(trapMsg, 'public')
   pMod.apiMessage.setPDU(trapMsg, trapPDU)

   transportDispatcher = AsyncoreDispatcher()

   # UDP/IPv4
   transportDispatcher.registerTransport(
       udp.domainName, udp.UdpSocketTransport().openClientMode()
   )
   transportDispatcher.sendMessage(
       encoder.encode(trapMsg), udp.domainName, ('demo.snmplabs.com', 162)
   )

   # UDP/IPv6
   transportDispatcher.registerTransport(
       udp6.domainName, udp6.Udp6SocketTransport().openClientMode()
   )
   transportDispatcher.sendMessage(
       encoder.encode(trapMsg), udp6.domainName, ('::1', 162)
   )

   ## Local domain socket
   # transportDispatcher.registerTransport(
   #    unix.domainName, unix.UnixSocketTransport().openClientMode()
   # )
   # transportDispatcher.sendMessage(
   #    encoder.encode(trapMsg), unix.domainName, '/tmp/snmp-manager'
   # )

   # Dispatcher will finish as all scheduled messages are sent
   transportDispatcher.runDispatcher()

   transportDispatcher.closeDispatcher()

"Download" script.


INFORM over multiple transports
===============================

The following script sends SNMP INFORM notification using the
following options:

* with SNMPv2c

* with community name 'public'

* over IPv4/UDP and IPv6/UDP

* send INFORM notification

* to a Manager at demo.snmplabs.com:162 and [::1]:162

* with TRAP ID 'coldStart' specified as an OID

The following Net-SNMP command will produce similar SNMP notification:

   $ snmpinform -v2c -c public udp:demo.snmplabs.com 0 1.3.6.1.6.3.1.1.5.1
   $ snmpinform -v2c -c public udp6:[::1] 0 1.3.6.1.6.3.1.1.5.1

   from time import time
   from pysnmp.carrier.asynsock.dispatch import AsynsockDispatcher
   from pysnmp.carrier.asynsock.dgram import udp, udp6
   from pyasn1.codec.ber import encoder, decoder
   from pysnmp.proto.api import v2c as pMod

   # Build PDU
   reqPDU = pMod.InformRequestPDU()
   pMod.apiTrapPDU.setDefaults(reqPDU)

   # Build message
   trapMsg = pMod.Message()
   pMod.apiMessage.setDefaults(trapMsg)
   pMod.apiMessage.setCommunity(trapMsg, 'public')
   pMod.apiMessage.setPDU(trapMsg, reqPDU)

   startedAt = time()


   def cbTimerFun(timeNow):
       if timeNow - startedAt > 3:
           raise Exception("Request timed out")


   # noinspection PyUnusedLocal,PyUnusedLocal
   def cbRecvFun(transportDispatcher, transportDomain, transportAddress,
                 wholeMsg, reqPDU=reqPDU):
       while wholeMsg:
           rspMsg, wholeMsg = decoder.decode(wholeMsg, asn1Spec=pMod.Message())
           rspPDU = pMod.apiMessage.getPDU(rspMsg)
           # Match response to request
           if pMod.apiPDU.getRequestID(reqPDU) == pMod.apiPDU.getRequestID(rspPDU):
               # Check for SNMP errors reported
               errorStatus = pMod.apiPDU.getErrorStatus(rspPDU)
               if errorStatus:
                   print(errorStatus.prettyPrint())
               else:
                   print('INFORM message delivered, response var-binds follow')
                   for oid, val in pMod.apiPDU.getVarBinds(rspPDU):
                       print('%s = %s' % (oid.prettyPrint(), val.prettyPrint()))
               transportDispatcher.jobFinished(1)
       return wholeMsg


   transportDispatcher = AsynsockDispatcher()

   transportDispatcher.registerRecvCbFun(cbRecvFun)
   transportDispatcher.registerTimerCbFun(cbTimerFun)

   # UDP/IPv4
   transportDispatcher.registerTransport(
       udp.domainName, udp.UdpSocketTransport().openClientMode()
   )
   transportDispatcher.sendMessage(
       encoder.encode(trapMsg), udp.domainName, ('demo.snmplabs.com', 162)
   )
   transportDispatcher.jobStarted(1)

   # UDP/IPv6
   # transportDispatcher.registerTransport(
   #    udp6.domainName, udp6.Udp6SocketTransport().openClientMode()
   # )
   # transportDispatcher.sendMessage(
   #    encoder.encode(trapMsg), udp6.domainName, ('::1', 162)
   # )
   # transportDispatcher.jobStarted(1)

   # Dispatcher will finish as all scheduled messages are sent
   transportDispatcher.runDispatcher()

   transportDispatcher.closeDispatcher()

"Download" script.

See also: library reference.
