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


Serving multiple network interfaces
===================================

Receive SNMP TRAP/INFORM messages with the following options:

* SNMPv1/SNMPv2c

* with SNMP community "public"

* over IPv4/UDP, listening at 127.0.0.1:162 over IPv4/UDP, listening
  at 127.0.0.1:2162

* print received data on stdout

Either of the following Net-SNMP commands will send notifications to
this receiver:

   $ snmptrap -v2c -c public 127.0.0.1:162 123 1.3.6.1.6.3.1.1.5.1 1.3.6.1.2.1.1.5.0 s test
   $ snmpinform -v2c -c public 127.0.0.1:2162 123 1.3.6.1.6.3.1.1.5.1

   from pysnmp.entity import engine, config
   from pysnmp.carrier.asyncore.dgram import udp
   from pysnmp.entity.rfc3413 import ntfrcv

   # Create SNMP engine with autogenernated engineID and pre-bound
   # to socket transport dispatcher
   snmpEngine = engine.SnmpEngine()

   # Transport setup

   # UDP over IPv4, first listening interface/port
   config.addTransport(
       snmpEngine,
       udp.domainName + (1,),
       udp.UdpTransport().openServerMode(('127.0.0.1', 162))
   )

   # UDP over IPv4, second listening interface/port
   config.addTransport(
       snmpEngine,
       udp.domainName + (2,),
       udp.UdpTransport().openServerMode(('127.0.0.1', 2162))
   )

   # SNMPv1/2c setup

   # SecurityName <-> CommunityName mapping
   config.addV1System(snmpEngine, 'my-area', 'public')


   # Callback function for receiving notifications
   # noinspection PyUnusedLocal,PyUnusedLocal,PyUnusedLocal
   def cbFun(snmpEngine, stateReference, contextEngineId, contextName,
             varBinds, cbCtx):
       print('Notification from ContextEngineId "%s", ContextName "%s"' % (contextEngineId.prettyPrint(),
                                                                           contextName.prettyPrint()))
       for name, val in varBinds:
           print('%s = %s' % (name.prettyPrint(), val.prettyPrint()))


   # Register SNMP Application at the SNMP engine
   ntfrcv.NotificationReceiver(snmpEngine, cbFun)

   snmpEngine.transportDispatcher.jobStarted(1)  # this job would never finish

   # Run I/O dispatcher which would receive queries and send confirmations
   try:
       snmpEngine.transportDispatcher.runDispatcher()
   except:
       snmpEngine.transportDispatcher.closeDispatcher()
       raise

"Download" script.


Using multiple network transports
=================================

Receive SNMP TRAP/INFORM messages with the following options:

* SNMPv1/SNMPv2c

* with SNMP community "public"

* over IPv4/UDP, listening at 127.0.0.1:162 over IPv6/UDP, listening
  at [::1]:162

* print received data on stdout

Either of the following Net-SNMP commands will send notifications to
this receiver:

   $ snmptrap -v1 -c public 127.0.0.1 1.3.6.1.4.1.20408.4.1.1.2 127.0.0.1 1 1 123 1.3.6.1.2.1.1.1.0 s test
   $ snmptrap -v2c -c public udp6:[::1]:162 123 1.3.6.1.6.3.1.1.5.1 1.3.6.1.2.1.1.5.0 s test
   $ snmpinform -v2c -c public 127.0.0.1 123 1.3.6.1.6.3.1.1.5.1

   from pysnmp.entity import engine, config
   from pysnmp.carrier.asyncore.dgram import udp, udp6
   from pysnmp.entity.rfc3413 import ntfrcv

   # Create SNMP engine with autogenernated engineID and pre-bound
   # to socket transport dispatcher
   snmpEngine = engine.SnmpEngine()

   # Transport setup

   # UDP over IPv4
   config.addTransport(
       snmpEngine,
       udp.domainName,
       udp.UdpTransport().openServerMode(('127.0.0.1', 162))
   )

   # UDP over IPv6
   config.addTransport(
       snmpEngine,
       udp6.domainName,
       udp6.Udp6Transport().openServerMode(('::1', 162))
   )

   # SNMPv1/2c setup

   # SecurityName <-> CommunityName mapping
   config.addV1System(snmpEngine, 'my-area', 'public')


   # Callback function for receiving notifications
   # noinspection PyUnusedLocal,PyUnusedLocal,PyUnusedLocal
   def cbFun(snmpEngine, stateReference, contextEngineId, contextName,
             varBinds, cbCtx):
       print('Notification from ContextEngineId "%s", ContextName "%s"' % (contextEngineId.prettyPrint(),
                                                                           contextName.prettyPrint()))
       for name, val in varBinds:
           print('%s = %s' % (name.prettyPrint(), val.prettyPrint()))


   # Register SNMP Application at the SNMP engine
   ntfrcv.NotificationReceiver(snmpEngine, cbFun)

   snmpEngine.transportDispatcher.jobStarted(1)  # this job would never finish

   # Run I/O dispatcher which would receive queries and send confirmations
   try:
       snmpEngine.transportDispatcher.runDispatcher()
   except:
       snmpEngine.transportDispatcher.closeDispatcher()
       raise

"Download" script.


Receive notifications noting peer address
=========================================

Receive SNMP TRAP/INFORM messages with the following options:

* SNMPv1/SNMPv2c

* with SNMP community "public"

* over IPv4/UDP, listening at 127.0.0.1:162

* use observer facility to pull lower-level request details from SNMP
  engine

* print received data on stdout

Either of the following Net-SNMP commands will send notifications to
this receiver:

   $ snmptrap -v2c -c public 127.0.0.1:162 123 1.3.6.1.6.3.1.1.5.1 1.3.6.1.2.1.1.5.0 s test

   from pysnmp.entity import engine, config
   from pysnmp.carrier.asyncore.dgram import udp
   from pysnmp.entity.rfc3413 import ntfrcv

   # Create SNMP engine with autogenernated engineID and pre-bound
   # to socket transport dispatcher
   snmpEngine = engine.SnmpEngine()

   # Transport setup

   # UDP over IPv4, first listening interface/port
   config.addTransport(
       snmpEngine,
       udp.domainName + (1,),
       udp.UdpTransport().openServerMode(('127.0.0.1', 162))
   )

   # SNMPv1/2c setup

   # SecurityName <-> CommunityName mapping
   config.addV1System(snmpEngine, 'my-area', 'public')


   # Callback function for receiving notifications
   # noinspection PyUnusedLocal,PyUnusedLocal
   def cbFun(snmpEngine, stateReference, contextEngineId, contextName,
             varBinds, cbCtx):
       # Get an execution context...
       execContext = snmpEngine.observer.getExecutionContext(
           'rfc3412.receiveMessage:request'
       )

       # ... and use inner SNMP engine data to figure out peer address
       print('Notification from %s, ContextEngineId "%s", ContextName "%s"' % ('@'.join([str(x) for x in execContext['transportAddress']]),
                                                                               contextEngineId.prettyPrint(),
                                                                               contextName.prettyPrint()))
       for name, val in varBinds:
           print('%s = %s' % (name.prettyPrint(), val.prettyPrint()))


   # Register SNMP Application at the SNMP engine
   ntfrcv.NotificationReceiver(snmpEngine, cbFun)

   snmpEngine.transportDispatcher.jobStarted(1)  # this job would never finish

   # Run I/O dispatcher which would receive queries and send confirmations
   try:
       snmpEngine.transportDispatcher.runDispatcher()
   except:
       snmpEngine.transportDispatcher.closeDispatcher()
       raise

"Download" script.

See also: library reference.
