将上下文名称添加到 snmp 代理是否有任何正确的格式？

Question

我是 SNMP 新手 Context.I 正在云中设置 SNMP 代理。这是我们从使用上下文名称的 snmplabs.com 中获得的基本格式。但问题是当我们在 snmpwalk 请求中使用上下文名称时，它会给出类似

的回复

"SNMPv2-SMI::dod = No more variables left in this MIB View (It is past the end of the MIB tree)"

我们遵循格式 http://snmplabs.com/pysnmp/examples/v3arch/asyncore/agent/cmdrsp/agent-side-mib-implementations.html

# Serve non-default MIB tree

# Listen and respond to SNMP GET / SET / GETNEXT / GETBULK queries with
# the following options:

#  SNMPv3
#  with USM username usr - md5 - none
#  using alternative set of Managed Objects addressed by
#  contextName: my - context
#  allow access to SNMPv2 - MIB objects (1.3.6.1.2.1)
#  over IPv4 / UDP, listening at 127.0.0.1:161

from pysnmp.entity import engine, config

from pysnmp.entity.rfc3413 import cmdrsp, context

from pysnmp.carrier.asyncore.dgram import udp

from pysnmp.smi import instrum, builder

from pysnmp.proto.api import v2c

snmpEngine = engine.SnmpEngine()

config.addTransport(
    snmpEngine,
    udp.domainName,
    udp.UdpTransport().openServerMode(('127.0.0.1', 161))
)

# SNMPv3/USM setup

# user: usr-md5-none, auth: MD5, priv NONE
config.addV3User(
    snmpEngine, 'usr-md5-none',
    config.usmHMACMD5AuthProtocol, 'authkey1'
)

# Allow full MIB access for each user at VACM
config.addVacmUser(snmpEngine, 3, 'usr-md5-none', 'authNoPriv', (1, 3, 6, 1, 2, 1), (1, 3, 6, 1, 2, 1))

snmpContext = context.SnmpContext(
    snmpEngine
)

# Create an [empty] set of Managed Objects (MibBuilder), pass it to
# Management Instrumentation Controller and register at SNMP Context
# under ContextName 'my-context'
snmpContext.registerContextName(
    v2c.OctetString('my-context'),  # Context Name
    instrum.MibInstrumController(builder.MibBuilder().loadModules)  # Managed Objects
)

# Register SNMP Applications at the SNMP engine for particular SNMP context
cmdrsp.GetCommandResponder(snmpEngine, snmpContext)
cmdrsp.SetCommandResponder(snmpEngine, snmpContext)
cmdrsp.NextCommandResponder(snmpEngine, snmpContext)
cmdrsp.BulkCommandResponder(snmpEngine, snmpContext)

# Register an imaginary never-ending job to keep I/O dispat#cher running forever
snmpEngine.transportDispatcher.jobStarted(1)

# Run I/O dispatcher which would receive queries and send responses
try:
    snmpEngine.transportDispatcher.runDispatcher()
except:
    snmpEngine.transportDispatcher.closeDispatcher()
    raise

snmpwalk -v3 -u usr-md5-none -l authNoPriv -A authkey1  -n my-context 127.0.0.1 .1.3.6

使用上面的snmpwalk，我们会得到类似

的输出

SNMPv2-SMI::dod = No more variables left in this MIB View (It is past the end of the MIB tree)

但是如果使用下面的snmpwalk

snmpwalk -v3 -u usr-md5-none -l authNoPriv -A authkey1 127.0.0.1 .1.3.6

我们将得到输出

SNMPv2-MIB::sysDescr.0 = STRING: PySNMP engine version 4.4.11, Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:24:40) [MSC v.1500 64 bit (AMD64)]

SNMPv2-MIB::sysObjectID.0 = OID: SNMPv2-SMI::enterprises.20408
DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (14) 0:00:00.14

SNMPv2-MIB::sysContact.0 = STRING:

SNMPv2-MIB::sysName.0 = STRING: 
SNMPv2-MIB::sysLocation.0 = STRING: 
SNMPv2-MIB::sysServices.0 = INTEGER: 0
SNMPv2-MIB::sysORLastChange.0 = Timeticks: (0) 0:00:00.00
SNMPv2-MIB::snmpInPkts.0 = Counter32: 10
SNMPv2-MIB::snmpOutPkts.0 = Counter32: 0
SNMPv2-MIB::snmpInBadVersions.0 = Counter32: 0
SNMPv2-MIB::snmpInBadCommunityNames.0 = Counter32: 0
SNMPv2-MIB::snmpInBadCommunityUses.0 = Counter32: 0
SNMPv2-MIB::snmpInASNParseErrs.0 = Counter32: 0
SNMPv2-MIB::snmpInTooBigs.0 = Counter32: 0
SNMPv2-MIB::snmpInNoSuchNames.0 = Counter32: 0
SNMPv2-MIB::snmpInBadValues.0 = Counter32: 0
SNMPv2-MIB::snmpInReadOnlys.0 = Counter32: 0
SNMPv2-MIB::snmpInGenErrs.0 = Counter32: 0
SNMPv2-MIB::snmpInTotalReqVars.0 = Counter32: 0
SNMPv2-MIB::snmpInTotalSetVars.0 = Counter32: 0
SNMPv2-MIB::snmpInGetRequests.0 = Counter32: 0
SNMPv2-MIB::snmpInGetNexts.0 = Counter32: 0
SNMPv2-MIB::snmpInGetResponses.0 = Counter32: 0
SNMPv2-MIB::snmpInTraps.0 = Counter32: 0
SNMPv2-MIB::snmpOutTooBigs.0 = Counter32: 0
SNMPv2-MIB::snmpOutNoSuchNames.0 = Counter32: 0
SNMPv2-MIB::snmpOutBadValues.0 = Counter32: 0
SNMPv2-MIB::snmpOutGenErrs.0 = Counter32: 0
SNMPv2-MIB::snmpOutSetRequests.0 = Counter32: 0
SNMPv2-MIB::snmpOutGetResponses.0 = Counter32: 0
SNMPv2-MIB::snmpOutTraps.0 = Counter32: 0
SNMPv2-MIB::snmpEnableAuthenTraps.0 = INTEGER: enabled(1)
SNMPv2-MIB::snmpSilentDrops.0 = Counter32: 0
SNMPv2-MIB::snmpProxyDrops.0 = Counter32: 0

因此，为了获得相同的上下文名称输出，我应该注意哪些更改

Answer 1

您是否填充了 MIB？这一行：

instrum.MibInstrumController(builder.MibBuilder())  # Managed Objects

创建一个空的 MIB 树并将其注册到 my-context 上下文名称下。除非您在代码的其他地方填充该 MIB 树，否则这就解释了为什么您没有收到任何响应。

如果你这样做：

instrum.MibInstrumController(builder.MibBuilder().loadModules())

pysnmp 搜索路径中的所有现有 MIB 模块都将加载并注册到这个新的 MIB 树中。

顺便说一句，整个 ContextEngineId 配置与 ContextName 无关。除非您出于某种原因需要它，否则您可以在代码中删除与特定 ContextEngineId 值相关的所有内容。

将上下文名称添加到 snmp 代理是否有任何正确的格式？

Is there any right format for adding context name to the snmp agent?

python

snmp

net-snmp

pysnmp