使用PySNMP作为具有自己/供应商MIB的陷阱接收器

Question

我尝试使用PySNMP接收SNMPv3陷阱。我找到了这个示例代码：

#!/usr/bin/env /usr/bin/python3

from pysnmp.entity import engine, config
from pysnmp.carrier.asyncore.dgram import udp
from pysnmp.entity.rfc3413 import ntfrcv
from pysnmp.proto.api import v2c
from pysnmp.smi.rfc1902 import ObjectIdentity

snmpEngine = engine.SnmpEngine()

# Transport setup

# UDP over IPv4
config.addTransport(
    snmpEngine,
    udp.domainName,
    udp.UdpTransport().openServerMode(('0.0.0.0', 162)),
)

# SNMPv3/USM setup
config.addV3User(
    snmpEngine, '<username>',
    config.usmHMACMD5AuthProtocol, '<password>',
    config.usmAesCfb128Protocol, '<password>',
    securityEngineId=v2c.OctetString(hexValue='<engineid>')
)

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

这段代码适合我，但我得到了原始陷阱。我有一个我想要使用的特定于供应商的MIB文件。但我找不到任何文档如何将mib绑定到snmpEngine。使用PySNMP文档中的MIB的示例仅显示SNMP GET操作的用法，此处不适用。有人试过这个并且可以帮助我吗？

谢谢！

Answer 1

如果你的目标是解决原始的变量绑定，你会收到人类友好的形式，那么你需要通过MIB浏览器对象process这些变量绑定。

你是对的，这与命令生成器在示例中经常执行的操作完全相同。

from pysnmp.smi import builder, view, compiler, rfc1902

# Assemble MIB browser
mibBuilder = builder.MibBuilder()
mibViewController = view.MibViewController(mibBuilder)
compiler.addMibCompiler(
    mibBuilder, sources=['file:///usr/share/snmp/mibs',
                         'http://mibs.snmplabs.com/asn1/@mib@'])

# Pre-load MIB modules that define objects we receive in TRAPs
mibBuilder.loadModules('SNMPv2-MIB', 'SNMP-COMMUNITY-MIB')

# This is what we would get in a TRAP PDU
varBinds = [
    ('1.3.6.1.2.1.1.3.0', 12345),
    ('1.3.6.1.6.3.1.1.4.1.0', '1.3.6.1.6.3.1.1.5.2'),
    ('1.3.6.1.6.3.18.1.3.0', '0.0.0.0'),
    ('1.3.6.1.6.3.18.1.4.0', ''),
    ('1.3.6.1.6.3.1.1.4.3.0', '1.3.6.1.4.1.20408.4.1.1.2'),
    ('1.3.6.1.2.1.1.1.0', 'my system')
]

# Pass raw var-binds through MIB browser
varBinds = [
    rfc1902.ObjectType(rfc1902.ObjectIdentity(x[0]), x[1]).resolveWithMib(mibViewController)
    for x in varBinds
]

for varBind in varBinds:
    print(varBind.prettyPrint())