我正在尝试编写一个 python SNMP 代理，我可以将其嵌入到我的 python 应用程序中，以便可以通过 OpenNMS 远程监控该应用程序。 OpenNMS 期望 Agent 实现HOST-RESOURCES-MIB查询两个字段hrSWRunNameand hrSWRunStatus.
我以 pysnmp 示例作为代码的基础，并根据需要对其进行了编辑。结果代码如下所示：
import logging
from pysnmp import debug
from pysnmp.carrier.asyncore.dgram import udp
from pysnmp.entity import engine, config
from pysnmp.entity.rfc3413 import cmdrsp, context
from pysnmp.proto.api import v2c
from pysnmp.smi import builder, instrum, exval
# debug.setLogger(debug.Debug('all'))
formatting = '[%(asctime)s-%(levelname)s]-(%(module)s) %(message)s'
logging.basicConfig(level=logging.DEBUG, format=formatting, )
logging.info("Starting....")
# Create SNMP engine
snmpEngine = engine.SnmpEngine()
# Transport setup
# UDP over IPv4
config.addTransport(
snmpEngine,
udp.domainName,
udp.UdpTransport().openServerMode(('localhost', 12345))
)
# 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, 1, 2, 1),
(1, 3, 6, 1, 2, 1))
# Create an SNMP context
snmpContext = context.SnmpContext(snmpEngine)
logging.debug('Loading HOST-RESOURCES-MIB module...'),
mibBuilder = builder.MibBuilder().loadModules('HOST-RESOURCES-MIB')
logging.debug('done')
logging.debug('Building MIB tree...'),
mibInstrum = instrum.MibInstrumController(mibBuilder)
logging.debug('done')
logging.debug('Building table entry index from human-friendly representation...')
# see http://www.oidview.com/mibs/0/HOST-RESOURCES-MIB.html
hostRunTable, = mibBuilder.importSymbols('HOST-RESOURCES-MIB', 'hrSWRunEntry')
instanceId = hostRunTable.getInstIdFromIndices(1)
logging.debug('done')
# The following shows the OID name mapping
#
# hrSWRunTable 1.3.6.1.2.1.25.4.2 <TABLE>
# hrSWRunEntry 1.3.6.1.2.1.25.4.2.1 <SEQUENCE>
# hrSWRunIndex 1.3.6.1.2.1.25.4.2.1.1 <Integer32>
# hrSWRunName 1.3.6.1.2.1.25.4.2.1.2 <InternationalDisplayString> 64 Char
# hrSWRunID 1.3.6.1.2.1.25.4.2.1.3 <ProductID>
# hrSWRunPath 1.3.6.1.2.1.25.4.2.1.4 <InternationalDisplayString> 128 octets
# hrSWRunParameters 1.3.6.1.2.1.25.4.2.1.5 <InternationalDisplayString> 128 octets
# hrSWRunType 1.3.6.1.2.1.25.4.2.1.6 <INTEGER>
# hrSWRunStatus 1.3.6.1.2.1.25.4.2.1.7 <INTEGER> <<===== This is the key variable used by Opennms
# http://docs.opennms.org/opennms/releases/18.0.1/guide-admin/guide-admin.html#_hostresourceswrunmonitor)
logging.debug('Create/update HOST-RESOURCES-MIB::hrSWRunTable table row:')
varBinds = mibInstrum.writeVars((
(hostRunTable.name + (1,) + instanceId, 1),
(hostRunTable.name + (2,) + instanceId, 'AppName'), # <=== Must match OpenNMS service-name variable
(hostRunTable.name + (3,) + instanceId, {0,0}), #
(hostRunTable.name + (4,) + instanceId, 'All is well'),
(hostRunTable.name + (5,) + instanceId, 'If this was not the case it would say so here'),
(hostRunTable.name + (6,) + instanceId, 4),# Values are ==> unknown(1), operatingSystem(2), deviceDriver(3), application(4)
(hostRunTable.name + (7,) + instanceId, 1) #<<=== This is the status number OpenNMS looks at Values are ==> running(1), runnable(2), notRunnable(3), invalid(4)
))
for oid, val in varBinds:
print('%s = %s' % ('.'.join([str(x) for x in oid]), val.prettyPrint()))
logging.debug('done')
logging.debug('Read whole MIB (table walk)')
oid, val = (), None
while True:
oid, val = mibInstrum.readNextVars(((oid, val),))[0]
if exval.endOfMib.isSameTypeWith(val):
break
print('%s = %s' % ('.'.join([str(x) for x in oid]), val.prettyPrint()))
logging.debug('done')
# logging.debug('Unloading MIB modules...'),
# mibBuilder.unloadModules()
# logging.debug('done')
# --- end of table population ---
# 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 dispatcher 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
代码运行时不会产生错误。 varBinds 和 MIB Table walk 显示了我认为我应该期待的内容：
[2016-12-29 16:42:49,323-INFO]-(SNMPAgent) Starting....
[2016-12-29 16:42:49,470-DEBUG]-(SNMPAgent) Loading HOST-RESOURCES-MIB module...
[2016-12-29 16:42:49,631-DEBUG]-(SNMPAgent) done
[2016-12-29 16:42:49,631-DEBUG]-(SNMPAgent) Building MIB tree...
[2016-12-29 16:42:49,631-DEBUG]-(SNMPAgent) done
[2016-12-29 16:42:49,631-DEBUG]-(SNMPAgent) Building table entry index from human-friendly representation...
[2016-12-29 16:42:49,631-DEBUG]-(SNMPAgent) done
[2016-12-29 16:42:49,632-DEBUG]-(SNMPAgent) Create/update HOST-RESOURCES-MIB::hrSWRunTable table row:
1.3.6.1.2.1.25.4.2.1.1.1 = 1
[2016-12-29 16:42:49,651-DEBUG]-(SNMPAgent) done
1.3.6.1.2.1.25.4.2.1.2.1 = TradeLoader
1.3.6.1.2.1.25.4.2.1.3.1 = 0
1.3.6.1.2.1.25.4.2.1.4.1 = All is well
1.3.6.1.2.1.25.4.2.1.5.1 = If this was not the case it would say so here
1.3.6.1.2.1.25.4.2.1.6.1 = 'application'
1.3.6.1.2.1.25.4.2.1.7.1 = 'running'
[2016-12-29 16:42:49,651-DEBUG]-(SNMPAgent) Read whole MIB (table walk)
1.3.6.1.2.1.25.4.2.1.1.1 = 1
1.3.6.1.2.1.25.4.2.1.2.1 = TradeLoader
1.3.6.1.2.1.25.4.2.1.3.1 = 0
1.3.6.1.2.1.25.4.2.1.4.1 = All is well
1.3.6.1.2.1.25.4.2.1.5.1 = If this was not the case it would say so here
1.3.6.1.2.1.25.4.2.1.6.1 = 'application'
1.3.6.1.2.1.25.4.2.1.7.1 = 'running'
1.3.6.1.2.1.25.5.1.1.1.1 = <no value>
1.3.6.1.2.1.25.5.1.1.2.1 = <no value>
[2016-12-29 16:42:53,490-DEBUG]-(SNMPAgent) done
最后，调度程序启动。
问题是当我尝试查询代理时什么也没有发生。我没有得到任何回应。我查看了我的代码，一个明显的事实是我没有将 snmpEngine 显式链接到我创建的 MIB。我应该这样做吗？
任何见解都会受到极大的欢迎，因为我正在努力了解目前该去哪里。
