[snmp] SNMP Set Response is lost / packet dropped by Westhawk API

[Birgit Arkesteijn]

Hi,

This is not good news, it shouldn't happen.
I currently don't have much time to investigate, sorry, and problems 
like this are not easy to reproduce.

Which version of the stack are you using
and which SNMP version are you using?

Some background:
As soon as a SnmpContext sends a request, it's run() method will keep 
listening for incoming responses until destroy() is called. Dealing with 
the response is done on the receive thread.

It might be possible that the context misses an incoming request, 
however, the context retransmits the request a couple of times.
There could be a race condition.


Kevin,
The AsnObject class has a static method called setDebug.
If you call
   AsnObject.setDebug(11);
early on when using the stack, it will print out (amongst many other 
things) every message the SnmpContext receives.

It won't fix your problem, but it will tell you if the stack receives 
the response at the lower level, but somehow not deals with it higher up.

Could you look into it and let us know your findings?

Thanks, Birgit



On 30/05/08 22:07, Josh Bers wrote:
> I too have noticed problems with set requests on the stack when attempting
> to change snmpv3 passwords using the USM mib, RFC 3414...
> 
> -----Original Message-----
> From: snmp-bounces at snmp.westhawk.co.uk
> [mailto:snmp-bounces at snmp.westhawk.co.uk] On Behalf Of Kevin Bond
> Sent: Friday, May 30, 2008 5:37 AM
> To: snmp at snmp.westhawk.co.uk
> Subject: [snmp] SNMP Set Response is lost / packet dropped by Westhawk API
> 
> 
> Hi,
> 
>      I have been using WestHawk SNMP API for few years now.     Currently I
> am facing a peculiar packet loss issue.
> 
>      I have a program that sends a series of set requests to an SNMP
> device. All the set-requests work perfectly in standalone. When executed one
> after another, they execute successfully 5 out of six times in the other
> instance I get a Timeout exception in a Random place.
> 
> When I attempted to trace the packets with Wireshark (assuming that it is a
> device problem) I noticed that the response for the set request was properly
> received by the machine immediately, but It was not captured by the
> particular Westhawk session.
> 
> I am not sure how to fine tune the WestHawk API to prevent it from dropping
> any packets. Thanks, Kevin 
 >

-- 
-- Birgit Arkesteijn, birgit at westhawk.co.uk,
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