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#
# Notification Originator
#
# Send SNMP notifications in behalf of multiple independend SNMP engines
# using the following options:
#
# * with a single transport dispatcher and two independent SNMP engines
# * SNMPv2c and SNMPv3
# * with community name 'public' or USM username usr-md5-des
# * over IPv4/UDP
# * send IMFORM notification
# * to multiple Managers
# * with TRAP ID 'coldStart' specified as a MIB symbol
# * include managed object information specified as var-bind objects pair
#
# Within this script we have a single asynchronous TransportDispatcher
# and a single UDP-based transport serving two independent SNMP engines.
# We use a single instance of AsyncNotificationOriginator with each of
# SNMP Engines to communicate INFORM notification to remote systems.
#
# When we receive a [response] message from remote system we use
# a custom message router to choose what of the two SNMP engines
# data packet should be handed over. The selection criteria we
# employ here is based on peer's UDP port number. Other selection
# criterias are also possible.
#
from pysnmp.entity.rfc3413.oneliner import ntforg
from pysnmp.entity import engine
from pysnmp.entity.rfc3413 import context
from pysnmp.carrier.asynsock.dispatch import AsynsockDispatcher
from pysnmp.proto import rfc1902
# List of targets in the following format:
# ( ( authData, transportTarget ), ... )
targets = (
# 1-st target (SNMPv2c over IPv4/UDP)
( ntforg.CommunityData('public'),
ntforg.UdpTransportTarget(('localhost', 1162)) ),
# 2-nd target (SNMPv3 over IPv4/UDP)
( ntforg.UsmUserData('usr-md5-des', 'authkey1', 'privkey1'),
ntforg.UdpTransportTarget(('localhost', 162)) )
)
def cbFun(snmpEngine, sendRequestHandle, errorIndication,
errorStatus, errorIndex, varBinds, cbCtx):
snmpEngine = cbCtx
if errorIndication:
print('Notification %s for %s not sent: %s' % (sendRequestHandle, snmpEngine.snmpEngineID.prettyPrint(), errorIndication))
elif errorStatus:
print('Notification Receiver returned error for request %s, SNMP Engine %s: %s @%s' % (sendRequestHandle, snmpEngine.snmpEngineID.prettyPrint(), errorStatus, errorIndex))
else:
print('Notification %s for SNMP Engine %s delivered:' % (sendRequestHandle, snmpEngine.snmpEngineID.prettyPrint()))
for name, val in varBinds:
print('%s = %s' % (name.prettyPrint(), val.prettyPrint()))
# Instantiate the single transport dispatcher object
transportDispatcher = AsynsockDispatcher()
# Setup a custom data routing function to select snmpEngine by transportDomain
transportDispatcher.registerRoutingCbFun(
lambda td,ta,d: ta[1] % 3 and 'A' or 'B'
)
snmpEngineA = engine.SnmpEngine()
snmpEngineA.registerTransportDispatcher(transportDispatcher, 'A')
snmpEngineB = engine.SnmpEngine()
snmpEngineB.registerTransportDispatcher(transportDispatcher, 'B')
ntfOrg = ntforg.AsyncNotificationOriginator()
for authData, transportTarget in targets:
snmpEngine = transportTarget.getTransportInfo()[1][1] % 3 and \
snmpEngineA or snmpEngineB
sendPduHandle = ntfOrg.sendNotification(
snmpEngine,
context.SnmpContext(snmpEngine),
authData,
transportTarget,
ntforg.ContextData(),
'inform',
ntforg.MibVariable('SNMPv2-MIB', 'coldStart'),
( ( rfc1902.ObjectName('1.3.6.1.2.1.1.1.0'),
rfc1902.OctetString('my name') ), ),
cbInfo=(cbFun, snmpEngine)
)
transportDispatcher.runDispatcher()
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