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"""
Bulk walk Agent MIB (SNMPv2c)
+++++++++++++++++++++++++++++
Perform SNMP GETBULK operation with the following options:
* with SNMPv2c, community 'public'
* over IPv4/UDP
* to an Agent at 195.218.195.228:161
* for OID in tuple form
* with non-repeaters=0 and max-repeaters=25
This script performs similar to the following Net-SNMP command:
| $ snmpbulkwalk -v2c -c public -ObentU -Cn0 -Cr25 195.218.195.228 1.3.6
"""#
from pysnmp.carrier.asyncore.dispatch import AsyncoreDispatcher
from pysnmp.carrier.asyncore.dgram import udp
from pyasn1.codec.ber import encoder, decoder
from pysnmp.proto.api import v2c
from time import time
# SNMP table header
headVars = [ v2c.ObjectIdentifier((1,3,6)) ]
# Build PDU
reqPDU = v2c.GetBulkRequestPDU()
v2c.apiBulkPDU.setDefaults(reqPDU)
v2c.apiBulkPDU.setNonRepeaters(reqPDU, 0)
v2c.apiBulkPDU.setMaxRepetitions(reqPDU, 25)
v2c.apiBulkPDU.setVarBinds(reqPDU, [ (x, v2c.null) for x in headVars ])
# Build message
reqMsg = v2c.Message()
v2c.apiMessage.setDefaults(reqMsg)
v2c.apiMessage.setCommunity(reqMsg, 'public')
v2c.apiMessage.setPDU(reqMsg, reqPDU)
startedAt = time()
def cbTimerFun(timeNow):
if timeNow - startedAt > 3:
raise Exception("Request timed out")
def cbRecvFun(transportDispatcher, transportDomain, transportAddress,
wholeMsg, reqPDU=reqPDU, headVars=headVars):
while wholeMsg:
rspMsg, wholeMsg = decoder.decode(wholeMsg, asn1Spec=v2c.Message())
rspPDU = v2c.apiMessage.getPDU(rspMsg)
# Match response to request
if v2c.apiBulkPDU.getRequestID(reqPDU)==v2c.apiBulkPDU.getRequestID(rspPDU):
# Format var-binds table
varBindTable = v2c.apiBulkPDU.getVarBindTable(reqPDU, rspPDU)
# Check for SNMP errors reported
errorStatus = v2c.apiBulkPDU.getErrorStatus(rspPDU)
if errorStatus and errorStatus != 2:
errorIndex = v2c.apiBulkPDU.getErrorIndex(rspPDU)
print('%s at %s' % (errorStatus.prettyPrint(),
errorIndex and varBindTable[int(errorIndex)-1] or '?'))
transportDispatcher.jobFinished(1)
break
# Report SNMP table
for tableRow in varBindTable:
for name, val in tableRow:
print('from: %s, %s = %s' % (
transportAddress, name.prettyPrint(), val.prettyPrint()
)
)
# Stop on EOM
for oid, val in varBindTable[-1]:
if not isinstance(val, v2c.Null):
break
else:
transportDispatcher.jobFinished(1)
# Generate request for next row
v2c.apiBulkPDU.setVarBinds(
reqPDU, [ (x, v2c.null) for x,y in varBindTable[-1] ]
)
v2c.apiBulkPDU.setRequestID(reqPDU, v2c.getNextRequestID())
transportDispatcher.sendMessage(
encoder.encode(reqMsg), transportDomain, transportAddress
)
global startedAt
if time() - startedAt > 3:
raise Exception('Request timed out')
startedAt = time()
return wholeMsg
transportDispatcher = AsyncoreDispatcher()
transportDispatcher.registerRecvCbFun(cbRecvFun)
transportDispatcher.registerTimerCbFun(cbTimerFun)
transportDispatcher.registerTransport(
udp.domainName, udp.UdpSocketTransport().openClientMode()
)
transportDispatcher.sendMessage(
encoder.encode(reqMsg), udp.domainName, ('demo.snmplabs.com', 161)
)
transportDispatcher.jobStarted(1)
# Dispatcher will finish as job#1 counter reaches zero
transportDispatcher.runDispatcher()
transportDispatcher.closeDispatcher()
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