pysnmp-dev — PySNMP development

Re: [Pysnmp-dev] error in parsing mibs using build-pysnmp-mibs and loading mibs using pysnmp

[Ilya E. <il...@gl...>]

This is most likely a MIB / smidump issue.

Could you please send it to me for further analysis?

-ilya

On May 27, 2011, at 10:02 PM, Karan Thakral <kar...@gm...>  
wrote:

> hi
>
> I am new person to pysnmp.
>
> I am trying to load some custom mibs using mib builder.
>
> Initially as per the pysnmp documentation i used the build-pysnmp- 
> mib utility for converting the mibs to pysnmp mib format.But i get  
> the following error from pysnmp.smi import builder
>
> Empty input smidump -f python hpicfvg.mib | libsmi2pysnmp fails
>
> Also with using the -k option smidump generates a file but the  
> mibBuilder is not able to load the generated file.
>
> I read somewhere that there are bugs in the implementation but  
> cannot find enough documentation or examples on the internet
>
> Thanks
>
>  Karan
>
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[Pysnmp-dev] error in parsing mibs using build-pysnmp-mibs and loading mibs using pysnmp

[Karan T. <kar...@gm...>]

hi

I am new person to pysnmp.

I am trying to load some custom mibs using mib builder.

Initially as per the pysnmp documentation i used the build-pysnmp-mib
utility for converting the mibs to pysnmp mib format.But i get the following
error from pysnmp.smi import builder

Empty input smidump -f python hpicfvg.mib | libsmi2pysnmp fails

Also with using the -k option smidump generates a file but the mibBuilder is
not able to load the generated file.

I read somewhere that there are bugs in the implementation but cannot find
enough documentation or examples on the internet

Thanks

 Karan

Re: [Pysnmp-dev] Doubt regarding SNMPv3 Agent setup using PYSNMP

[Ilya E. <il...@gl...>]

BTW, pysnmp code that is currently in CVS will not crash SNMP engine
in case of a misconfiguration like you seem to have.

-ilya

>      pysnmp/v4/proto/secmod/rfc3414/auth/base.py", line .., in
> authenticateIncomingMsg
> ProtocolError: no authentication

Re: [Pysnmp-dev] Doubt regarding SNMPv3 Agent setup using PYSNMP

[Ilya E. <il...@gl...>]

Mohammed,

Your Manager might be querying using authentication option (e.g. 
authNoPriv or authPriv) while your Agent does not have a user configured 
with authentication option enabled. So, doublecheck that.

BTW, in your example there seems to be a typo in username - 'test-uset'
instead of 'test-user'.

-ilya

>               Just one help needed regarding SNMPv3 set for agent. I
> used the example given in the link:
>
> http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html
>
> Though v1, v2 are working fine as I have tested with (Free PowerSNMP
> Manager) by discovering and sending queries. But when I tried doing so
> with SNMPv3 set up by configuring noAuthNoPriv (no authentication, no
> privacy), Manager is failing to discover the agent and agent throwing
> error while discovery message is being processed on agent. The error is
>
> Traceback (most recent call last):
>
> /pysnmp/v4/carrier/asynsock/dispatch.py", line 60, in runDispatcher
>
> :              :              :
>
> :              :              :
>
> pysnmp/v4/carrier/asynsock/dgram/base.py", line .., in handle_read
>
> pysnmp/v4/carrier/base.py", line .., in _cbFun
>
>  pysnmp/v4/entity/engine.py", line .., in __receiveMessageCbFun
>
>   pysnmp/v4/proto/rfc3412.py", line ..., in receiveMessage
>
>    pysnmp/v4/proto/mpmod/rfc3412.py", line ..., in prepareDataElements
>
>     pysnmp/v4/proto/secmod/rfc3414/service.py", line ..., in
> processIncomingMsg
>
>      pysnmp/v4/proto/secmod/rfc3414/auth/base.py", line .., in
> authenticateIncomingMsg
>
> ProtocolError: no authentication
>
>
>
> I modified the example only for ip address, used no authentication and
> no privacy for v3 as shown here:
>
> config.addV3User(
>
>     snmpEngine, 'test-uset',
>
>     config.usmNoAuthProtocol, None,
>
>     config.usmNoPrivProtocol, None
>
>     )
>
> :
>
> config.addRwUser(snmpEngine, 3, 'test-user', 'noAuthNoPriv', (1,3,6)) #
> v3
>
> And for discovery, I have used the following configuration on SNMP
> Manager (powerSNMP Manager):
> SNMP Version: Three
> Security-level : None (other options: auth, authpriv)
> Username: test-user
>
> Please have a look and suggest me where I am missing, or let me know if
> my setup/configurations are not OK.

[Pysnmp-dev] Doubt regarding SNMPv3 Agent setup using PYSNMP

[Mohammed A. (mdaahad) <md...@ci...>]

Hi Ilya,

               Just one help needed regarding SNMPv3 set for agent. I
used the example given in the link:

http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html

Though v1, v2 are working fine as I have tested with (Free PowerSNMP
Manager) by discovering and sending queries. But when I tried doing so
with SNMPv3 set up by configuring noAuthNoPriv (no authentication, no
privacy), Manager is failing to discover the agent and agent throwing
error while discovery message is being processed on agent. The error is

Traceback (most recent call last):

/pysnmp/v4/carrier/asynsock/dispatch.py", line 60, in runDispatcher

:              :              :

:              :              :

pysnmp/v4/carrier/asynsock/dgram/base.py", line .., in handle_read

 pysnmp/v4/carrier/base.py", line .., in _cbFun

  pysnmp/v4/entity/engine.py", line .., in __receiveMessageCbFun

   pysnmp/v4/proto/rfc3412.py", line ..., in receiveMessage

    pysnmp/v4/proto/mpmod/rfc3412.py", line ..., in prepareDataElements

     pysnmp/v4/proto/secmod/rfc3414/service.py", line ..., in
processIncomingMsg

      pysnmp/v4/proto/secmod/rfc3414/auth/base.py", line .., in
authenticateIncomingMsg

ProtocolError: no authentication

 

I modified the example only for ip address, used no authentication and
no privacy for v3 as shown here:

config.addV3User(

     snmpEngine, 'test-uset',

     config.usmNoAuthProtocol, None,

     config.usmNoPrivProtocol, None

     )

:

config.addRwUser(snmpEngine, 3, 'test-user', 'noAuthNoPriv', (1,3,6)) #
v3
 
And for discovery, I have used the following configuration on SNMP
Manager (powerSNMP Manager):
SNMP Version: Three
Security-level : None (other options: auth, authpriv)
Username: test-user
 
Please have a look and suggest me where I am missing, or let me know if
my setup/configurations are not OK.
 
Thanks,
Mohammed

 

Re: [Pysnmp-dev] Regarding pysnmp/entity/engine.py : AttributeError: 'module' object has no attribute 'ProtocolError'

[Ilya E. <il...@gl...>]

Mohammed,

You seem to run into a bug/typo. Patch is attached to this message
and it's also in CVS at SF.

You can modify and use pysnmp in any way.

However it surprises me that you have to use pysnmp at relatively low 
API level. Maybe your goal could be satisfied on top of high-level API
(which is more stable and easy to use).

Therefore, once you consider sharing the details of your project, I 
could possibly advise on the best approach.

-ilya

>               I am getting error when I use certain functions in
> engine.py file like registerTransportDispatcher for the module 'error'
> which is imported from pysnmp/error.py which has only one attribute
> PySnmpError, the we are trying to call ProtocolError which is there in
> pysnmp/proto/error.py. I believe we can change the code as per the
> license agreement but I want to know if I am missing something or some
> patch. Can you please clarify in this ?

Re: [Pysnmp-dev] Need information on SNMP Agent implementation usingPYSNMP

[Ilya E. <il...@gl...>]

Mohammed,

> 	With reference to your example given in the following link:
> http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html
>
> I want to know two facts, once you start your engine, which API in that
> example is kind of a blocking call or the API which just listens for
> GET/other requests from other devices ? and will get invoked only when
> there is request (GET/SET) received ?

In current implementation, everything revolves around the main loop
which is invoked by:

snmpEngine.transportDispatcher.runDispatcher()

call and terminates only on SNMP engine shutdown.

All other API functions/methods are either explicitly invoked before 
starting the main loop (mostly configuration settings) or called back 
from the mail loop on message arrival (MIB objects, in my example).

Listening and processing incoming messages is hidden behind the API we are 
talking about here.

> Once we have our own mapping with the real life objects and we have
> fetched the real value after getting GET request, Which API of cmd
> responder is preparing to send the response? (I can see the registration
> but I don't see any mechanism there which prepares the response and send
> it to the ip/device which has sent the request).

With pysnmp's built-in SMI subsystem, you can intercept individual MIB 
object access using this code:

# Override readGet method and return file content
class MyFileReadingMibObject(MibScalarInstance):
   def readGet(self, name, *args):
     return name, rfc1902.OctetString(open('/etc/passwd').read())

# attach new object to MIB tree (you must also export its parent object)
mibBuilder.exportSymbols(
     "__MYFILEREADING-MIB",
     MyFileReadingMibObject(
           (1, 3, 6, 1, 2, 1, 1, 2, 1), (0,), rfc1902.OctetString()
     )
)

Now when you do:

snmpget -v2c -c public localhost 1.3.6.1.2.1.1.2.1.0

the return would be your /etc/passwd file content.

Message preparing and sending is done automatically my SNMP engine -- you 
only have to return a value from your object's readGet() method.

Keep in mind, that the readGet() method is currently synchronous -- you 
can't block in there or the whole SNMP engine would block.

If fetching a value is going to take time, an asynchronous implementation
is also possible.

-ilya

> -----Original Message-----
> From: Ilya Etingof [mailto:il...@gl...]
> Sent: Monday, November 01, 2010 9:56 PM
> To: Mohammed Ahad (mdaahad)
> Cc: Pys...@li...
> Subject: RE: [Pysnmp-dev] Need information on SNMP Agent implementation
> usingPYSNMP
>
>
>> 1. once we start our engine, how can we listen (continuously) to the
>> GET/SET requests received from other devices(may be a manager) ?
>
> Yes, sure you can. Here's a working example of an Agent:
>
> http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html
>
>> 2. I could not understand the mapping of the instances to real life
>> objects, can you explain it briefly.
>
> What is your real-life setup? Knowing this would help me advise you the
> best possible solution.
>
> Conceptually, pysnmp Agent talks to a SMI (MIB) subsystem through a very
>
> simple API (pysnmp.smi.MibInstrumController methods) to either fetch or
> modify/create OID-value pairs.
>
> You can implement your own MIB backend and plug it into stock pysnmp
> Agent. By way of example, this approach is used in the SNMP Simulator
> software:
>
> http://sourceforge.net/projects/snmpsim/
>
> Or you could use stock pysnmp SMI subsystem by
>
> 1) subclassing MibScalarInstance class and overloading its
>    read*/write* methods
>
> or
>
> 2) subclassing SNMP data type classes (Integer, OctetString, IpAddress
>    etc.), overloading their clone() method and attaching these
> customized
>    objects to MibScalarInstance.syntax attribute.
>
> Here's a more in-depth discussion on the topic:
>
> http://sourceforge.net/mailarchive/forum.php?thread_name=4C00CD1E.609060
> 0%40akimeka.com&forum_name=pysnmp-users
>
>> 3. My implementation is about to add a support for SNMP agent where I
>> have few MIBS. I want to add the SNMP agent support first then SNMP
>> Manager support using PYSNMP. I have MIBs which are in xxx-MIB.py
> form.
>
> With pysnmp you could implement Manager, Agent or Manager+Agent
> kinds of applications. All scenarious support MIB backend (Agent
> role) and MIB resolution (Manager role).
>
> If you have more specific questions, please, let me know.
>
> -ilya
>
>> -----Original Message-----
>> From: Ilya Etingof [mailto:il...@gl...]
>> Sent: Friday, October 29, 2010 2:56 AM
>> To: Mohammed Ahad (mdaahad)
>> Cc: Pys...@li...
>> Subject: Re: [Pysnmp-dev] Need information on SNMP Agent
> implementation
>> usingPYSNMP
>>
>>
>> There is a brief tutorial on Agent-side MIB support:
>>
>> http://pysnmp.sourceforge.net/docs/4.x/index.html#MIB-SERVICES
>>
>> All the low-level SNMP operations (like loading MIB backend, decoding
>> SNMP
>> queries etc) are hidden inside the CommandResponder application:
>>
>> http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html
>>
>> which is already a fully functional SNMP Agent.
>>
>> What might take most of your efforts is bridging your Managed
>> Objects (this is what you are going to manage though SNMP) with
>> pysnmp's MIB API.
>>
>> One approach is explained in the Agent application above, which
>> is hooking on MibScalarInstance's "syntax" component. Though, there
>> are a few others.
>>
>> If you explain your goal in more details, I'd be able to advise.
>>
>> -ilya
>>
>>> Moreover I need info on the requirements and infrastructure component
>>> details that are essential to respond to SNMP Query, for example, how
>>> can we start SNMP engine and how the MIB file (XXX-MIB.py) exports
> the
>>> symbols and how can it decode the SNMP Get Query and how can we
> listen
>>> to the queries.
>>>
>>>               I need some good documentation on SNMP agent side
>>> implementation using PYSNMP, or if someone guide me with a good
>> example
>>> (along with explanation) will be appreciable.
>>
>>
>
>

[Pysnmp-dev] Regarding pysnmp/entity/engine.py : AttributeError: 'module' object has no attribute 'ProtocolError'

[Mohammed A. (mdaahad) <md...@ci...>]

Hi Ilya,

               I am getting error when I use certain functions in
engine.py file like registerTransportDispatcher for the module 'error'
which is imported from pysnmp/error.py which has only one attribute
PySnmpError, the we are trying to call ProtocolError which is there in
pysnmp/proto/error.py. I believe we can change the code as per the
license agreement but I want to know if I am missing something or some
patch. Can you please clarify in this ?

 

Thanks,

Mohammed A Ahad

Re: [Pysnmp-dev] Need information on SNMP Agent implementation usingPYSNMP

[Mohammed A. (mdaahad) <md...@ci...>]

Hi Ilya,
	With reference to your example given in the following link:
http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html

I want to know two facts, once you start your engine, which API in that
example is kind of a blocking call or the API which just listens for
GET/other requests from other devices ? and will get invoked only when
there is request (GET/SET) received ?

Once we have our own mapping with the real life objects and we have
fetched the real value after getting GET request, Which API of cmd
responder is preparing to send the response? (I can see the registration
but I don't see any mechanism there which prepares the response and send
it to the ip/device which has sent the request).

Thanks for your patience,
M A Ahad



-----Original Message-----
From: Ilya Etingof [mailto:il...@gl...] 
Sent: Monday, November 01, 2010 9:56 PM
To: Mohammed Ahad (mdaahad)
Cc: Pys...@li...
Subject: RE: [Pysnmp-dev] Need information on SNMP Agent implementation
usingPYSNMP


> 1. once we start our engine, how can we listen (continuously) to the
> GET/SET requests received from other devices(may be a manager) ?

Yes, sure you can. Here's a working example of an Agent:

http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html

> 2. I could not understand the mapping of the instances to real life
> objects, can you explain it briefly.

What is your real-life setup? Knowing this would help me advise you the 
best possible solution.

Conceptually, pysnmp Agent talks to a SMI (MIB) subsystem through a very

simple API (pysnmp.smi.MibInstrumController methods) to either fetch or 
modify/create OID-value pairs.

You can implement your own MIB backend and plug it into stock pysnmp 
Agent. By way of example, this approach is used in the SNMP Simulator
software:

http://sourceforge.net/projects/snmpsim/

Or you could use stock pysnmp SMI subsystem by

1) subclassing MibScalarInstance class and overloading its
    read*/write* methods

or

2) subclassing SNMP data type classes (Integer, OctetString, IpAddress
    etc.), overloading their clone() method and attaching these
customized
    objects to MibScalarInstance.syntax attribute.

Here's a more in-depth discussion on the topic:

http://sourceforge.net/mailarchive/forum.php?thread_name=4C00CD1E.609060
0%40akimeka.com&forum_name=pysnmp-users

> 3. My implementation is about to add a support for SNMP agent where I
> have few MIBS. I want to add the SNMP agent support first then SNMP
> Manager support using PYSNMP. I have MIBs which are in xxx-MIB.py
form.

With pysnmp you could implement Manager, Agent or Manager+Agent 
kinds of applications. All scenarious support MIB backend (Agent 
role) and MIB resolution (Manager role).

If you have more specific questions, please, let me know.

-ilya

> -----Original Message-----
> From: Ilya Etingof [mailto:il...@gl...]
> Sent: Friday, October 29, 2010 2:56 AM
> To: Mohammed Ahad (mdaahad)
> Cc: Pys...@li...
> Subject: Re: [Pysnmp-dev] Need information on SNMP Agent
implementation
> usingPYSNMP
>
>
> There is a brief tutorial on Agent-side MIB support:
>
> http://pysnmp.sourceforge.net/docs/4.x/index.html#MIB-SERVICES
>
> All the low-level SNMP operations (like loading MIB backend, decoding
> SNMP
> queries etc) are hidden inside the CommandResponder application:
>
> http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html
>
> which is already a fully functional SNMP Agent.
>
> What might take most of your efforts is bridging your Managed
> Objects (this is what you are going to manage though SNMP) with
> pysnmp's MIB API.
>
> One approach is explained in the Agent application above, which
> is hooking on MibScalarInstance's "syntax" component. Though, there
> are a few others.
>
> If you explain your goal in more details, I'd be able to advise.
>
> -ilya
>
>> Moreover I need info on the requirements and infrastructure component
>> details that are essential to respond to SNMP Query, for example, how
>> can we start SNMP engine and how the MIB file (XXX-MIB.py) exports
the
>> symbols and how can it decode the SNMP Get Query and how can we
listen
>> to the queries.
>>
>>               I need some good documentation on SNMP agent side
>> implementation using PYSNMP, or if someone guide me with a good
> example
>> (along with explanation) will be appreciable.
>
>

Re: [Pysnmp-dev] Need information on SNMP Agent implementation usingPYSNMP

[Ilya E. <il...@gl...>]

> 1. once we start our engine, how can we listen (continuously) to the
> GET/SET requests received from other devices(may be a manager) ?

Yes, sure you can. Here's a working example of an Agent:

http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html

> 2. I could not understand the mapping of the instances to real life
> objects, can you explain it briefly.

What is your real-life setup? Knowing this would help me advise you the 
best possible solution.

Conceptually, pysnmp Agent talks to a SMI (MIB) subsystem through a very 
simple API (pysnmp.smi.MibInstrumController methods) to either fetch or 
modify/create OID-value pairs.

You can implement your own MIB backend and plug it into stock pysnmp 
Agent. By way of example, this approach is used in the SNMP Simulator
software:

http://sourceforge.net/projects/snmpsim/

Or you could use stock pysnmp SMI subsystem by

1) subclassing MibScalarInstance class and overloading its
    read*/write* methods

or

2) subclassing SNMP data type classes (Integer, OctetString, IpAddress
    etc.), overloading their clone() method and attaching these customized
    objects to MibScalarInstance.syntax attribute.

Here's a more in-depth discussion on the topic:

http://sourceforge.net/mailarchive/forum.php?thread_name=4C00CD1E.6090600%40akimeka.com&forum_name=pysnmp-users

> 3. My implementation is about to add a support for SNMP agent where I
> have few MIBS. I want to add the SNMP agent support first then SNMP
> Manager support using PYSNMP. I have MIBs which are in xxx-MIB.py form.

With pysnmp you could implement Manager, Agent or Manager+Agent 
kinds of applications. All scenarious support MIB backend (Agent 
role) and MIB resolution (Manager role).

If you have more specific questions, please, let me know.

-ilya

> -----Original Message-----
> From: Ilya Etingof [mailto:il...@gl...]
> Sent: Friday, October 29, 2010 2:56 AM
> To: Mohammed Ahad (mdaahad)
> Cc: Pys...@li...
> Subject: Re: [Pysnmp-dev] Need information on SNMP Agent implementation
> usingPYSNMP
>
>
> There is a brief tutorial on Agent-side MIB support:
>
> http://pysnmp.sourceforge.net/docs/4.x/index.html#MIB-SERVICES
>
> All the low-level SNMP operations (like loading MIB backend, decoding
> SNMP
> queries etc) are hidden inside the CommandResponder application:
>
> http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html
>
> which is already a fully functional SNMP Agent.
>
> What might take most of your efforts is bridging your Managed
> Objects (this is what you are going to manage though SNMP) with
> pysnmp's MIB API.
>
> One approach is explained in the Agent application above, which
> is hooking on MibScalarInstance's "syntax" component. Though, there
> are a few others.
>
> If you explain your goal in more details, I'd be able to advise.
>
> -ilya
>
>> Moreover I need info on the requirements and infrastructure component
>> details that are essential to respond to SNMP Query, for example, how
>> can we start SNMP engine and how the MIB file (XXX-MIB.py) exports the
>> symbols and how can it decode the SNMP Get Query and how can we listen
>> to the queries.
>>
>>               I need some good documentation on SNMP agent side
>> implementation using PYSNMP, or if someone guide me with a good
> example
>> (along with explanation) will be appreciable.
>
>

Re: [Pysnmp-dev] Need information on SNMP Agent implementation usingPYSNMP

[Mohammed A. (mdaahad) <md...@ci...>]

Hi Ilya,
	Thank you very much for the quick response. I have been through
those useful documents, but still I have few doubts:
1. once we start our engine, how can we listen (continuously) to the
GET/SET requests received from other devices(may be a manager) ?
2. I could not understand the mapping of the instances to real life
objects, can you explain it briefly.
3. My implementation is about to add a support for SNMP agent where I
have few MIBS. I want to add the SNMP agent support first then SNMP
Manager support using PYSNMP. I have MIBs which are in xxx-MIB.py form.

Once again thanks for the quick response and waiting for the specific
response to my queries.

Thanks,
M A Ahad

-----Original Message-----
From: Ilya Etingof [mailto:il...@gl...] 
Sent: Friday, October 29, 2010 2:56 AM
To: Mohammed Ahad (mdaahad)
Cc: Pys...@li...
Subject: Re: [Pysnmp-dev] Need information on SNMP Agent implementation
usingPYSNMP


There is a brief tutorial on Agent-side MIB support:

http://pysnmp.sourceforge.net/docs/4.x/index.html#MIB-SERVICES

All the low-level SNMP operations (like loading MIB backend, decoding
SNMP 
queries etc) are hidden inside the CommandResponder application:

http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html

which is already a fully functional SNMP Agent.

What might take most of your efforts is bridging your Managed 
Objects (this is what you are going to manage though SNMP) with
pysnmp's MIB API.

One approach is explained in the Agent application above, which 
is hooking on MibScalarInstance's "syntax" component. Though, there
are a few others.

If you explain your goal in more details, I'd be able to advise.

-ilya

> Moreover I need info on the requirements and infrastructure component
> details that are essential to respond to SNMP Query, for example, how
> can we start SNMP engine and how the MIB file (XXX-MIB.py) exports the
> symbols and how can it decode the SNMP Get Query and how can we listen
> to the queries.
>
>               I need some good documentation on SNMP agent side
> implementation using PYSNMP, or if someone guide me with a good
example
> (along with explanation) will be appreciable.

Re: [Pysnmp-dev] Need information on SNMP Agent implementation usingPYSNMP

[Ilya E. <il...@gl...>]

There is a brief tutorial on Agent-side MIB support:

http://pysnmp.sourceforge.net/docs/4.x/index.html#MIB-SERVICES

All the low-level SNMP operations (like loading MIB backend, decoding SNMP 
queries etc) are hidden inside the CommandResponder application:

http://pysnmp.sourceforge.net/examples/4.x/v3arch/agent/cmdrsp.html

which is already a fully functional SNMP Agent.

What might take most of your efforts is bridging your Managed 
Objects (this is what you are going to manage though SNMP) with
pysnmp's MIB API.

One approach is explained in the Agent application above, which 
is hooking on MibScalarInstance's "syntax" component. Though, there
are a few others.

If you explain your goal in more details, I'd be able to advise.

-ilya

> Moreover I need info on the requirements and infrastructure component
> details that are essential to respond to SNMP Query, for example, how
> can we start SNMP engine and how the MIB file (XXX-MIB.py) exports the
> symbols and how can it decode the SNMP Get Query and how can we listen
> to the queries.
>
>               I need some good documentation on SNMP agent side
> implementation using PYSNMP, or if someone guide me with a good example
> (along with explanation) will be appreciable.

Re: [Pysnmp-dev] Need information on SNMP Agent implementation usingPYSNMP

[Mohammed A. (mdaahad) <md...@ci...>]

Moreover I need info on the requirements and infrastructure component
details that are essential to respond to SNMP Query, for example, how
can we start SNMP engine and how the MIB file (XXX-MIB.py) exports the
symbols and how can it decode the SNMP Get Query and how can we listen
to the queries.

 

Thanks in advance,

M A Ahad

 

From: Mohammed Ahad (mdaahad) 
Sent: Thursday, October 28, 2010 8:54 PM
To: Pys...@li...
Subject: [Pysnmp-dev] Need information on SNMP Agent implementation
usingPYSNMP

 

Hi All,

               I need some good documentation on SNMP agent side
implementation using PYSNMP, or if someone guide me with a good example
(along with explanation) will be appreciable.

 

Thanks,

M A Ahad

[Pysnmp-dev] Need information on SNMP Agent implementation using PYSNMP

[Mohammed A. (mdaahad) <md...@ci...>]

Hi All,

               I need some good documentation on SNMP agent side
implementation using PYSNMP, or if someone guide me with a good example
(along with explanation) will be appreciable.

 

Thanks,

M A Ahad

Re: [Pysnmp-dev] Definition of Opaque class

[Ilya E. <il...@gl...>]

You seem to be correct. That's a bug in pysnmp code. I have just 
fixed it in CVS at SF.

But how did you notice it? Did it break something to SNMP message 
decoding?

thanks,
ilya

> I believe that definition of this class should be:
>
> class Opaque(univ.OctetString):
>    tagSet = univ.OctetString.tagSet.tagImplicitly(
>        tag.Tag(tag.tagClassApplication, tag.tagFormatSimple, 0x04)
>        )
>
> Am I correct?

[Pysnmp-dev] Definition of Opaque class

[Fero K. <fer...@gm...>]

Hi,

I am new to PySNMP, I am trying to use it in my application.

I am unsure, whether definition of following class in
pysnmp/proto/rfc1155.py is correct:

class Opaque(univ.OctetString):
    tagSet = univ.Integer.tagSet.tagImplicitly(
        tag.Tag(tag.tagClassApplication, tag.tagFormatSimple, 0x04)
        )

Definition of Opaque in RFC 1155 is:

3.2.3.6.  Opaque   This application-wide type supports the capability
to pass arbitrary
   ASN.1 syntax.  A value is encoded using the ASN.1 basic rules into a
   string of octets.  This, in turn, is encoded as an OCTET STRING, in
   effect "double-wrapping" the original ASN.1 value.

I believe that definition of this class should be:

class Opaque(univ.OctetString):
    tagSet = univ.OctetString.tagSet.tagImplicitly(
        tag.Tag(tag.tagClassApplication, tag.tagFormatSimple, 0x04)
        )

Am I correct?
**
Fero

Re: [Pysnmp-dev] pysnmp v2 and examples

[Ilya E. <il...@gl...>]

There are no issues with v2c protocol support.

I'd suggest you starting with SNMPv3 architecture, which is easier 
to use and supports v1, v2c and v3 protocol versions.

See comments in this script for protocol version selection:

http://pysnmp.sourceforge.net/examples/4.x/v3arch/oneliner/manager/getgen.html

-ilya

> I am new to SNMP and pysnmp. I find on the project home page there is only
> examples for v1 and v3. No V2 examples, but if I type 2.x in the address
> bar, I can find these example for v2c.
>
> Since I will begin test  a V2 agent using pysnmp examples, I wonder if there
> is any issues with v2c?

[Pysnmp-dev] pysnmp v2 and examples

[frank z. <fra...@gm...>]

Hi,
I am new to SNMP and pysnmp. I find on the project home page there is only
examples for v1 and v3. No V2 examples, but if I type 2.x in the address
bar, I can find these example for v2c.

Since I will begin test  a V2 agent using pysnmp examples, I wonder if there
is any issues with v2c?

Re: [Pysnmp-dev] Pavckacge problem in Ubuntu Karmic

[Ilya E. <il...@gl...>]

Since pysnmp 4.1.12a there is no v4 directory in the package. I suspect an 
error somewhere in your pysnmp distribution. Please, report this issue to
your pysnmp distribution supplier.

Meanwhile, I suggest using pysnmp (and pyasn1) source distributions from 
SourceForge.

In any case, the right way to import pysnmp modules, regardless of pysnmp 
version, is like:

from pysnmp.entity.rfc3413.oneliner import cmdgen, ntforg

-ilya

> there seems to be a problem in the pysnmp package coming with karmic
> koala. The ..../pymodules/pysnmp/ has to sub directorys v3 and v4. The
> Problem ist that the import module path of the scripts doesnt include
> this v4. So the import fails anytime.
>
> If i try to import pysnmp.v4.* then it fails with sub scripts
>
> >>> import pysnmp; print pysnmp.__file__
> /usr/lib/pymodules/python2.6/pysnmp/__init__.pyc
> >>> quit()
>
> from pysnmp.entity.rfc3413.oneliner import cmdgen, ntforg
>
> leads to
>
> Traceback (most recent call last):
>   File "check_apc.py", line 6, in <module>
>     from pysnmp.entity.rfc3413.oneliner import cmdgen, ntforg
> ImportError: No module named entity.rfc3413.oneliner

[Pysnmp-dev] Pavckacge problem in Ubuntu Karmic

[Joerg S. <joe...@df...>]

Hi all,

there seems to be a problem in the pysnmp package coming with karmic 
koala. The ..../pymodules/pysnmp/ has to sub directorys v3 and v4. The 
Problem ist that the import module path of the scripts doesnt include 
this v4. So the import fails anytime.

If i try to import pysnmp.v4.* then it fails with sub scripts

 >>> import pysnmp; print pysnmp.__file__
/usr/lib/pymodules/python2.6/pysnmp/__init__.pyc
 >>> quit()

from pysnmp.entity.rfc3413.oneliner import cmdgen, ntforg

leads to

Traceback (most recent call last):
   File "check_apc.py", line 6, in <module>
     from pysnmp.entity.rfc3413.oneliner import cmdgen, ntforg
ImportError: No module named entity.rfc3413.oneliner


Best Wishes

[Pysnmp-dev] Error in processPdu in rfc3413/cmdrsp.py

[<Chi...@L-...>]

I try to use commercial MIB browsers like winAgent and MG-SOFT to query
pysnmp agent.  It doesn't work.
But when I use pysnmp getgen oneliner in examples. It works.
I try to debug in site-packages\pysnmp\v4\entity\rfc3413\cmdrsp.py.
I try to print securityName and securityLevel at processPdu (line 79 in
the cmdrsp.py). 
If I use pysnmp getgen, it print out the securityName and securityLevel,
However when I use Commercial Browser, it never gets there, which means
processPdu is never called.
Anything wrong?
Thanks
Chi

Re: [Pysnmp-dev] Erreur dans la RFC1155-SMI.py

[Ilya E. <il...@gl...>]

Bonjour,

C'est un bogue qui a été déjà corrigé dans CVS. Svp, trouvez la 
version correcte attachée à ce message.

-ilya

>  File "/usr/lib/python2.5/site-packages/pysnmp/v4/smi/builder.py", line 85, in loadModules
>    'MIB module \"%s\" load error: %s' % (modPath, why)
> pysnmp.smi.error.SmiError: MIB module "/usr/lib/python2.5/site-packages/pysnmp/v4/smi/mibs/RFC1155-SMI.py" load error: name 'Unsigned32' is not defined
>
> L'erreur est déjà là à l'installation des sources, j'ai regardé dans l'archive et le fichier RFC1155-SMI.py contient déjà des types Unsigned32 qui ne sont pas importés. Dans les anciennes versions, c'est bien des Integer32.
>
> Extrait de RFC1155-SMI.py:
> # Imports
>
> ( Integer, ObjectIdentifier, OctetString, ) = mibBuilder.importSymbols("ASN1", "Integer", "ObjectIdentifier", "OctetString")
> ( Bits, Integer32, MibIdentifier, TimeTicks, ) = mibBuilder.importSymbols("SNMPv2-SMI", "Bits", "Integer32", "MibIdentifier", "TimeTicks")
>
> # Types
>
> class Counter(Unsigned32):
>    subtypeSpec = Unsigned32.subtypeSpec+constraint.ValueRangeConstraint(0,4294967295L)
>    pass
>
> class Gauge(Unsigned32):
>    subtypeSpec = Unsigned32.subtypeSpec+constraint.ValueRangeConstraint(0,4294967295L)
>    pass
>
> [.....]
>
> class TimeTicks(Unsigned32):
>    subtypeSpec = Unsigned32.subtypeSpec+constraint.ValueRangeConstraint(0,4294967295L)
>    pass
>
> On voit bien que le type Unsigned32 n'est pas importé.
>
> Je n'ai pas de problème avec ma MIB, c'est juste que la fonction 
> loadModules charge toutes les MIB du dossier dont celle qui est bugguée.
>
> Cordialement,
>
> Marion DELEY

Re: [Pysnmp-dev] Erreur dans la RFC1155-SMI.py

[Ilya E. <il...@gl...>]

Bonjour,

Pourriez-vous svp fournir la trace de pile ou le code d'exemple 
pour me laisser voir ce qui se produit?

Vous pourriez convertir MIB.txt en .py avec le & de smidump outils de 
pysnmp/outils/libsmi2pysnmp.

-ilya

> J'utilise actuellement pysnmp pour un manager SNMP en python et lorsque 
> j'utilise la fonction loadModules() du fichier builder.py, je récupère 
> une erreur sur les types de données déclarées dans cette version de la 
> RFC -> Unsigned32 au lieu de Integer32. En comparaison avec vos 
> anciennes versions, il se trouve qu'il y a une erreur dans les sources 
> de la v4.1.11a, le type Unsigned doit être remplacé par le type Integer. 
> Je ne sais pas comment vous convertissez vos MIB .txt en .py mais le 
> problème vient sûrement du générateur.

[Pysnmp-dev] Erreur dans la RFC1155-SMI.py

[<Mar...@fr...>]

Bonjour,

J'utilise actuellement pysnmp pour un manager SNMP en python et lorsque j'utilise la fonction loadModules() du fichier builder.py, je récupère une erreur sur les types de données déclarées dans cette version de la RFC -> Unsigned32 au lieu de Integer32. En comparaison avec vos anciennes versions, il se trouve qu'il y a une erreur dans les sources de la v4.1.11a, le type Unsigned doit être remplacé par le type Integer.
Je ne sais pas comment vous convertissez vos MIB .txt en .py mais le problème vient sûrement du générateur.

Cordialement,

DELEY Marion

Re: [Pysnmp-dev] IANA-CHARSET mib byte compilation problem - pysnmp-mibs 0.0.7a

[Martin J. <mh...@sw...>]

Ilya Etingof wrote:
> 
> It turned to be a bug triggered by changed MIB text file. This bug has 
> been fixed in CVS (and also accedentally released at PyPi). The fix went 
> to libsmi2pysnmp script, rebuilt MIB is attached to this message.

OK, thanks.  I'll attach the patch to the FreeBSD port as well.

Marty