在多线程环境中使用 pysnmp 的 SNMP 代理超时
SNMP Agent using pysnmp in a multithreaded environment Timeout
我正在尝试编写一个可用于监视我的 python 进程的 SNMP 代理。为此，我编写了一个 class，它使用 pysnmp 实现了 SNMP 代理。
这个代理的核心部分工作（即我可以使用 snmpwalk 来询问代理并且返回的数据是正确的）。为了允许我更新代理 MIB 值，我在它自己的线程中有 运行 dispatcher()。我的问题是，当我使用 snmpwalk 与代理交谈时会超时（snmpwalk 正确地遍历 MIB，但随后超时）。
有没有人知道我做错了什么？
代理代码如下：
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.smi import exval
import threading
formatting = '[%(asctime)s-%(levelname)s]-(%(module)s) %(message)s'
logging.basicConfig(level=logging.DEBUG, format=formatting, )
class SNMPAgent(object):
def _main(self):
logging.debug("Creating SNMP Agent....")
self._snmpEngine = engine.SnmpEngine()
config.addTransport(
self._snmpEngine,
udp.domainName,
udp.UdpTransport().openServerMode((self._agentHost, self._agentPort))
)
config.addV1System(self._snmpEngine, 'my-area', self._communityName)
config.addVacmUser(self._snmpEngine,
2,
'my-area',
'noAuthNoPriv',
(1, 3, 6),
(1, 3, 6))
snmpContext = context.SnmpContext(self._snmpEngine)
mibBuilder = snmpContext.getMibInstrum().getMibBuilder()
mibBuilder.loadModules('HOST-RESOURCES-MIB')
self._mibInstrum = snmpContext.getMibInstrum()
self._hostRunTable, = mibBuilder.importSymbols('HOST-RESOURCES-MIB', 'hrSWRunEntry')
self._instanceId = self._hostRunTable.getInstIdFromIndices(1)
# 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
self._setVars()
cmdrsp.GetCommandResponder(self._snmpEngine, snmpContext)
cmdrsp.SetCommandResponder(self._snmpEngine, snmpContext)
cmdrsp.NextCommandResponder(self._snmpEngine, snmpContext)
cmdrsp.BulkCommandResponder(self._snmpEngine, snmpContext)
def runAgent(self):
'''
Run the Agent
'''
t = threading.Thread(target=self._runAgentFunc, args = ())
t.daemon = True
t.start()
def _runAgentFunc(self):
try:
self._snmpEngine.transportDispatcher.jobStarted(1)
self._snmpEngine.transportDispatcher.runDispatcher()
except:
self._snmpEngine.transportDispatcher.closeDispatcher()
raise
def updateAgentStatus(self, runStatus, text1, text2):
self._mibDict = {"hrSWRunIndex" : 1,
"hrSWRunName" : self._name,
"hrSWRunID" : self._enterpriseMIB,
"hrSWRunPath" : text1[:128] if text1 is not None else '',
"hrSWRunParameters" : text2[:128] if text1 is not None else '',
"hrSWRunType" : 4,
"hrSWRunStatus" : 1
}
self._setVars()
def _setVars(self):
varBinds = self._mibInstrum.writeVars((
(self._hostRunTable.name + (1,) + self._instanceId, self._mibDict["hrSWRunIndex"]),
(self._hostRunTable.name + (2,) + self._instanceId, self._mibDict["hrSWRunName"]), # <=== Must match OpenNMS service-name variable
(self._hostRunTable.name + (3,) + self._instanceId, self._mibDict["hrSWRunID" ]), #
(self._hostRunTable.name + (4,) + self._instanceId, self._mibDict["hrSWRunPath"]),
(self._hostRunTable.name + (5,) + self._instanceId, self._mibDict["hrSWRunParameters"]),
(self._hostRunTable.name + (6,) + self._instanceId, self._mibDict["hrSWRunType"]), # Values are ==> unknown(1), operatingSystem(2), deviceDriver(3), application(4)
(self._hostRunTable.name + (7,) + self._instanceId, self._mibDict["hrSWRunStatus"]) #<<=== This is the status number OpenNMS looks at Values are ==> running(1), runnable(2), notRunnable(3), invalid(4)
))
def __init__(self, name, host, port, community, text1='Service up', text2=''):
'''
#=======================================================================
# Constructor
# name -- the (process) name the agent should publish (must match
# the openNMS name
# host -- the host name or ip the agent will run on
# port -- the port the snmp agent will listen on
# community -- the community name the agent will use (usually 'public')
# text1 -- the first status text string published (128 char max)
# text2 -- the second status text string published (128 char max)
#=======================================================================
'''
self._name = name
self._agentHost = host
self._agentPort = port
self._communityName = community
self._enterpriseMIB = (1, 3, 6, 1, 4, 1, 50000, 0) # Made up for now
self._mibInstrum = None
self._snmpEngine = None
self._dataChanged = False
self._mibDict = {"hrSWRunIndex" : 1,
"hrSWRunName" : self._name,
"hrSWRunID" : self._enterpriseMIB,
"hrSWRunPath" : text1[:128] if text1 is not None else '',
"hrSWRunParameters" : text2[:128] if text1 is not None else '',
"hrSWRunType" : 4,
"hrSWRunStatus" : 1
}
self._main()
我调用这段代码如下（这只是测试我可以更改状态）：
from SNMPAgent import SNMPAgent
from time import sleep
agent = SNMPAgent("test", "127.0.0.1", 12345, "public", "This is my test message 1", "This is my test message 2")
agent.runAgent()
sleep(10) # Wait for it to start
while True:
agent.updateAgentStatus(3, "Oh no", "Something is wrong!")
sleep(30)
agent.updateAgentStatus(2, "Whew", "Everything is fixed")
sleep(30)
要遍历我使用的代理 MIB：
snmpwalk -v 2c -c public -n my-context 127.0.0.1:12345 1.3.6.1.2.1.25.4.2
这显示数据正在更新，但在遍历 MIB 结束时，代理超时：
HOST-RESOURCES-MIB::hrSWRunIndex.1 = INTEGER: 1
HOST-RESOURCES-MIB::hrSWRunName.1 = STRING: "test"
HOST-RESOURCES-MIB::hrSWRunID.1 = OID: SNMPv2-SMI::enterprises.50000.0
HOST-RESOURCES-MIB::hrSWRunPath.1 = STRING: "Whew"
HOST-RESOURCES-MIB::hrSWRunParameters.1 = STRING: "Everything is fixed"
HOST-RESOURCES-MIB::hrSWRunType.1 = INTEGER: application(4)
HOST-RESOURCES-MIB::hrSWRunStatus.1 = INTEGER: running(1)
Timeout: No Response from 127.0.0.1:12345
启用 pysnmp 调试会显示由特定 OID 的未设置整数值引起的序列化错误：
[2017-01-13 02:05:18,387-DEBUG]-(debug) generateResponseMsg: Message:
version='version-2c'
community=public
data=PDUs:
response=ResponsePDU:
request-id=1950819527
error-status='noError'
error-index=0
variable-bindings=VarBindList:
VarBind:
name=1.3.6.1.2.1.25.5.1.1.1.1
=_BindValue:
value=ObjectSyntax:
simple=SimpleSyntax:
integer-value=<no value>
2017-01-13 02:05:18,387 pysnmp: generateResponseMsg: serialization failure: Uninitialized ASN.1 value ("__eq__" attribute looked up)
[2017-01-13 02:05:18,387-DEBUG]-(debug) generateResponseMsg: serialization failure: Uninitialized ASN.1 value ("__eq__" attribute looked up)
2017-01-13 02:05:18,388 pysnmp: StatusInformation: {'errorIndication': <pysnmp.proto.errind.SerializationError object at 0x10162f828>}
[2017-01-13 02:05:18,388-DEBUG]-(debug) StatusInformation: {'errorIndication': <pysnmp.proto.errind.SerializationError object at 0x10162f828>}
您应该确保为所有 non-defaulted SNMP table 列设置值。
附带说明一下，您似乎在没有显式同步的情况下从主线程和 SNMP 代理线程管理您的 MIB。这可能会导致竞争条件...
我正在尝试编写一个可用于监视我的 python 进程的 SNMP 代理。为此，我编写了一个 class，它使用 pysnmp 实现了 SNMP 代理。
这个代理的核心部分工作（即我可以使用 snmpwalk 来询问代理并且返回的数据是正确的）。为了允许我更新代理 MIB 值，我在它自己的线程中有 运行 dispatcher()。我的问题是，当我使用 snmpwalk 与代理交谈时会超时（snmpwalk 正确地遍历 MIB，但随后超时）。
有没有人知道我做错了什么？
代理代码如下：
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.smi import exval
import threading
formatting = '[%(asctime)s-%(levelname)s]-(%(module)s) %(message)s'
logging.basicConfig(level=logging.DEBUG, format=formatting, )
class SNMPAgent(object):
def _main(self):
logging.debug("Creating SNMP Agent....")
self._snmpEngine = engine.SnmpEngine()
config.addTransport(
self._snmpEngine,
udp.domainName,
udp.UdpTransport().openServerMode((self._agentHost, self._agentPort))
)
config.addV1System(self._snmpEngine, 'my-area', self._communityName)
config.addVacmUser(self._snmpEngine,
2,
'my-area',
'noAuthNoPriv',
(1, 3, 6),
(1, 3, 6))
snmpContext = context.SnmpContext(self._snmpEngine)
mibBuilder = snmpContext.getMibInstrum().getMibBuilder()
mibBuilder.loadModules('HOST-RESOURCES-MIB')
self._mibInstrum = snmpContext.getMibInstrum()
self._hostRunTable, = mibBuilder.importSymbols('HOST-RESOURCES-MIB', 'hrSWRunEntry')
self._instanceId = self._hostRunTable.getInstIdFromIndices(1)
# 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
self._setVars()
cmdrsp.GetCommandResponder(self._snmpEngine, snmpContext)
cmdrsp.SetCommandResponder(self._snmpEngine, snmpContext)
cmdrsp.NextCommandResponder(self._snmpEngine, snmpContext)
cmdrsp.BulkCommandResponder(self._snmpEngine, snmpContext)
def runAgent(self):
'''
Run the Agent
'''
t = threading.Thread(target=self._runAgentFunc, args = ())
t.daemon = True
t.start()
def _runAgentFunc(self):
try:
self._snmpEngine.transportDispatcher.jobStarted(1)
self._snmpEngine.transportDispatcher.runDispatcher()
except:
self._snmpEngine.transportDispatcher.closeDispatcher()
raise
def updateAgentStatus(self, runStatus, text1, text2):
self._mibDict = {"hrSWRunIndex" : 1,
"hrSWRunName" : self._name,
"hrSWRunID" : self._enterpriseMIB,
"hrSWRunPath" : text1[:128] if text1 is not None else '',
"hrSWRunParameters" : text2[:128] if text1 is not None else '',
"hrSWRunType" : 4,
"hrSWRunStatus" : 1
}
self._setVars()
def _setVars(self):
varBinds = self._mibInstrum.writeVars((
(self._hostRunTable.name + (1,) + self._instanceId, self._mibDict["hrSWRunIndex"]),
(self._hostRunTable.name + (2,) + self._instanceId, self._mibDict["hrSWRunName"]), # <=== Must match OpenNMS service-name variable
(self._hostRunTable.name + (3,) + self._instanceId, self._mibDict["hrSWRunID" ]), #
(self._hostRunTable.name + (4,) + self._instanceId, self._mibDict["hrSWRunPath"]),
(self._hostRunTable.name + (5,) + self._instanceId, self._mibDict["hrSWRunParameters"]),
(self._hostRunTable.name + (6,) + self._instanceId, self._mibDict["hrSWRunType"]), # Values are ==> unknown(1), operatingSystem(2), deviceDriver(3), application(4)
(self._hostRunTable.name + (7,) + self._instanceId, self._mibDict["hrSWRunStatus"]) #<<=== This is the status number OpenNMS looks at Values are ==> running(1), runnable(2), notRunnable(3), invalid(4)
))
def __init__(self, name, host, port, community, text1='Service up', text2=''):
'''
#=======================================================================
# Constructor
# name -- the (process) name the agent should publish (must match
# the openNMS name
# host -- the host name or ip the agent will run on
# port -- the port the snmp agent will listen on
# community -- the community name the agent will use (usually 'public')
# text1 -- the first status text string published (128 char max)
# text2 -- the second status text string published (128 char max)
#=======================================================================
'''
self._name = name
self._agentHost = host
self._agentPort = port
self._communityName = community
self._enterpriseMIB = (1, 3, 6, 1, 4, 1, 50000, 0) # Made up for now
self._mibInstrum = None
self._snmpEngine = None
self._dataChanged = False
self._mibDict = {"hrSWRunIndex" : 1,
"hrSWRunName" : self._name,
"hrSWRunID" : self._enterpriseMIB,
"hrSWRunPath" : text1[:128] if text1 is not None else '',
"hrSWRunParameters" : text2[:128] if text1 is not None else '',
"hrSWRunType" : 4,
"hrSWRunStatus" : 1
}
self._main()
我调用这段代码如下（这只是测试我可以更改状态）：
from SNMPAgent import SNMPAgent
from time import sleep
agent = SNMPAgent("test", "127.0.0.1", 12345, "public", "This is my test message 1", "This is my test message 2")
agent.runAgent()
sleep(10) # Wait for it to start
while True:
agent.updateAgentStatus(3, "Oh no", "Something is wrong!")
sleep(30)
agent.updateAgentStatus(2, "Whew", "Everything is fixed")
sleep(30)
要遍历我使用的代理 MIB：
snmpwalk -v 2c -c public -n my-context 127.0.0.1:12345 1.3.6.1.2.1.25.4.2
这显示数据正在更新，但在遍历 MIB 结束时，代理超时：
HOST-RESOURCES-MIB::hrSWRunIndex.1 = INTEGER: 1
HOST-RESOURCES-MIB::hrSWRunName.1 = STRING: "test"
HOST-RESOURCES-MIB::hrSWRunID.1 = OID: SNMPv2-SMI::enterprises.50000.0
HOST-RESOURCES-MIB::hrSWRunPath.1 = STRING: "Whew"
HOST-RESOURCES-MIB::hrSWRunParameters.1 = STRING: "Everything is fixed"
HOST-RESOURCES-MIB::hrSWRunType.1 = INTEGER: application(4)
HOST-RESOURCES-MIB::hrSWRunStatus.1 = INTEGER: running(1)
Timeout: No Response from 127.0.0.1:12345
启用 pysnmp 调试会显示由特定 OID 的未设置整数值引起的序列化错误：
[2017-01-13 02:05:18,387-DEBUG]-(debug) generateResponseMsg: Message:
version='version-2c'
community=public
data=PDUs:
response=ResponsePDU:
request-id=1950819527
error-status='noError'
error-index=0
variable-bindings=VarBindList:
VarBind:
name=1.3.6.1.2.1.25.5.1.1.1.1
=_BindValue:
value=ObjectSyntax:
simple=SimpleSyntax:
integer-value=<no value>
2017-01-13 02:05:18,387 pysnmp: generateResponseMsg: serialization failure: Uninitialized ASN.1 value ("__eq__" attribute looked up)
[2017-01-13 02:05:18,387-DEBUG]-(debug) generateResponseMsg: serialization failure: Uninitialized ASN.1 value ("__eq__" attribute looked up)
2017-01-13 02:05:18,388 pysnmp: StatusInformation: {'errorIndication': <pysnmp.proto.errind.SerializationError object at 0x10162f828>}
[2017-01-13 02:05:18,388-DEBUG]-(debug) StatusInformation: {'errorIndication': <pysnmp.proto.errind.SerializationError object at 0x10162f828>}
您应该确保为所有 non-defaulted SNMP table 列设置值。
附带说明一下，您似乎在没有显式同步的情况下从主线程和 SNMP 代理线程管理您的 MIB。这可能会导致竞争条件...