Walking operations

Bulk walk MIB

Send a series of SNMP GETBULK requests * with SNMPv2c, community ‘public’ * over IPv4/UDP * to an Agent at 104.236.166.95:161 * with values non-repeaters = 0, max-repetitions = 25 * for two OIDs in tuple form * stop on end-of-mib condition for both OIDs

This script performs similar to the following Net-SNMP command:

$ snmpbulkwalk -v2c -c public -C n0 -C r25 -ObentU 104.236.166.95 1.3.6.1.2.1.1 1.3.6.1.4.1.1
from pysnmp.entity import engine, config
from pysnmp.entity.rfc3413 import cmdgen
from pysnmp.carrier.asyncore.dgram import udp

# Create SNMP engine instance
snmpEngine = engine.SnmpEngine()

#
# SNMPv2c setup
#

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

# Specify security settings per SecurityName (SNMPv1 - 0, SNMPv2c - 1)
config.addTargetParams(snmpEngine, 'my-creds', 'my-area', 'noAuthNoPriv', 1)

#
# Setup transport endpoint and bind it with security settings yielding
# a target name
#

# UDP/IPv4
config.addTransport(
    snmpEngine,
    udp.domainName,
    udp.UdpSocketTransport().openClientMode()
)
config.addTargetAddr(
    snmpEngine, 'my-router',
    udp.domainName, ('104.236.166.95', 161),
    'my-creds'
)


# Error/response receiver
# noinspection PyUnusedLocal,PyUnusedLocal,PyUnusedLocal
def cbFun(snmpEngine, sendRequesthandle, errorIndication,
          errorStatus, errorIndex, varBindTable, cbCtx):
    if errorIndication:
        print(errorIndication)
        return  # stop on error
    if errorStatus:
        print('%s at %s' % (errorStatus.prettyPrint(),
                            errorIndex and varBindTable[-1][int(errorIndex) - 1][0] or '?'))
        return  # stop on error
    for varBindRow in varBindTable:
        for oid, val in varBindRow:
            print('%s = %s' % (oid.prettyPrint(), val.prettyPrint()))
    return True  # signal dispatcher to continue walking


# Prepare initial request to be sent
cmdgen.BulkCommandGenerator().sendVarBinds(
    snmpEngine,
    'my-router',
    None, '',  # contextEngineId, contextName
    0, 25,  # non-repeaters, max-repetitions
    [((1, 3, 6, 1, 2, 1, 1), None),
     ((1, 3, 6, 1, 4, 1, 1), None)],
    cbFun
)

# Run I/O dispatcher which would send pending queries and process responses
snmpEngine.transportDispatcher.runDispatcher()

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Fetch two subtrees in parallel

Send a series of SNMP GETNEXT requests with the following options:

  • with SNMPv1, community ‘public’
  • over IPv4/UDP
  • to an Agent at 104.236.166.95:161
  • for two OIDs in tuple form
  • stop on end-of-mib condition for both OIDs

This script performs similar to the following Net-SNMP command:

$ snmpwalk -v1 -c public -ObentU 104.236.166.95 1.3.6.1.2.1.1 1.3.6.1.4.1.1
from pysnmp.entity import engine, config
from pysnmp.carrier.asyncore.dgram import udp
from pysnmp.entity.rfc3413 import cmdgen

# Create SNMP engine instance
snmpEngine = engine.SnmpEngine()

#
# SNMPv1/2c setup
#

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

# Specify security settings per SecurityName (SNMPv1 - 0, SNMPv2c - 1)
config.addTargetParams(snmpEngine, 'my-creds', 'my-area', 'noAuthNoPriv', 0)

#
# Setup transport endpoint and bind it with security settings yielding
# a target name
#

# UDP/IPv4
config.addTransport(
    snmpEngine,
    udp.domainName,
    udp.UdpSocketTransport().openClientMode()
)
config.addTargetAddr(
    snmpEngine, 'my-router',
    udp.domainName, ('104.236.166.95', 161),
    'my-creds'
)


# Error/response receiver
# noinspection PyUnusedLocal,PyUnusedLocal,PyUnusedLocal
def cbFun(snmpEngine, sendRequestHandle, errorIndication,
          errorStatus, errorIndex, varBindTable, cbCtx):
    if errorIndication:
        print(errorIndication)
        return
    # SNMPv1 response may contain noSuchName error *and* SNMPv2c exception,
    # so we ignore noSuchName error here
    if errorStatus and errorStatus != 2:
        print('%s at %s' % (errorStatus.prettyPrint(),
                            errorIndex and varBindTable[-1][int(errorIndex) - 1][0] or '?'))
        return  # stop on error
    for varBindRow in varBindTable:
        for oid, val in varBindRow:
            print('%s = %s' % (oid.prettyPrint(), val.prettyPrint()))
    return 1  # signal dispatcher to continue


# Prepare initial request to be sent
cmdgen.NextCommandGenerator().sendVarBinds(
    snmpEngine,
    'my-router',
    None, '',  # contextEngineId, contextName
    [((1, 3, 6, 1, 2, 1, 1), None),
     ((1, 3, 6, 1, 4, 1, 1), None)],
    cbFun
)

# Run I/O dispatcher which would send pending queries and process responses
snmpEngine.transportDispatcher.runDispatcher()

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See also: library reference.