Agent-side MIB implementations¶
Implementing scalar MIB objects¶
Listen and respond to SNMP GET/SET/GETNEXT/GETBULK queries with the following options:
- SNMPv2c
- with SNMP community “public”
- serving custom Managed Object Instance defined within this script
- allow read access only to the subtree where the custom MIB object resides
- over IPv4/UDP, listening at 127.0.0.1:161
- using Twisted fraework for network transport
Either of the following Net-SNMP commands will walk this Agent:
$ snmpwalk -v2c -c public 127.0.0.1 .1.3.6
import sys
from twisted.internet import reactor
from pysnmp.entity import engine, config
from pysnmp.entity.rfc3413 import cmdrsp, context
from pysnmp.proto import rfc1902
from pysnmp.carrier.twisted.dgram import udp
# 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.DOMAIN_NAME,
udp.UdpTwistedTransport().openServerMode(('127.0.0.1', 161))
)
# SNMPv2c setup
# SecurityName <-> CommunityName mapping.
config.addV1System(snmpEngine, 'my-area', 'public')
# Allow read MIB access for this user / securityModels at VACM
config.addVacmUser(snmpEngine, 2, 'my-area', 'noAuthNoPriv', (1, 3, 6, 5))
# Create an SNMP context
snmpContext = context.SnmpContext(snmpEngine)
# --- create custom Managed Object Instance ---
mibBuilder = snmpContext.getMibInstrum().getMibBuilder()
MibScalar, MibScalarInstance = mibBuilder.importSymbols(
'SNMPv2-SMI', 'MibScalar', 'MibScalarInstance'
)
class MyStaticMibScalarInstance(MibScalarInstance):
# noinspection PyUnusedLocal,PyUnusedLocal
def getValue(self, name, idx):
return self.getSyntax().clone(
'Python %s running on a %s platform' % (sys.version, sys.platform)
)
mibBuilder.exportSymbols(
'__MY_MIB', MibScalar((1, 3, 6, 5, 1), rfc1902.OctetString()),
MyStaticMibScalarInstance((1, 3, 6, 5, 1), (0,), rfc1902.OctetString())
)
# --- end of Managed Object Instance initialization ----
# Register SNMP Applications at the SNMP engine for particular SNMP context
cmdrsp.GetCommandResponder(snmpEngine, snmpContext)
cmdrsp.NextCommandResponder(snmpEngine, snmpContext)
cmdrsp.BulkCommandResponder(snmpEngine, snmpContext)
# Run Twisted main loop
reactor.run()
Download
script.
See also: library reference.