R: Re: [SNMP4J] IllegalStateException in Snmp.send()

[Alberto]

Thanks a lot Frank for being so quick.
Before posting my message, I read all contributions in the mailing list about 
the topic, checked my code and I am reasonably sure no Snmp.close() is called.
I have a single static instance of Snmp used for all requests sent (from 
different threads) to the agents. Snmp session is allocated the first time and 
never closed (it dies together with the application). After allocating Snmp 
session the first time, Snmp.listen() is called.
There is another Snmp session allocated for trap receival. Again here Snmp.
listen() is called and it is closed at application shutdown.
So ... still dark from my side.
Question: is the Snmp.close() traced in snmp4j logs? Because I cannot see 
anything about that.
Moreover: is there any other possibility leading to the problem I described 
and related to a misuse of snmp4j lib from my side?

PS If you need complete snmp4j logs with debug level, tell me.

Ciao,
Alberto


>----Messaggio originale----
>Dal: fock at agentpp.com
>Data: 14/12/2006 0.55
>A: "Alberto"<alberto_mascheroni at fastwebnet.it>
>Cc: <snmp4j at agentpp.org>
>Ogg: Re: [SNMP4J] IllegalStateException in Snmp.send()
>
>Hello Alberto,
>
>You wrote that you had to restart your application
>in order to use your Snmp instance again after
>having caught the error below. This indicates,
>that the timer referred to in the exception,
>had been canceled. That means that your code
>somewhere called Snmp.close() while requests
>where pending.
>
>That is how it is supposed to work: If you close
>the Snmp instance, then it is shutdown and
>cannot be used again. You will need to instantiate
>a new Snmp instance.
>
>So please do not call Snmp.close() between two
>queries!
>
>Hope this helps.
>
>Best regards,
>Frank
>
>Alberto wrote:
>> Hello,
>> I refer to the correction provided in v1.7.1 and described by Frank in 
email 
>> below.
>> Since I got the same problem in my project, I downloaded the SNMP4J 
version 
>> 1.7.5 and reproduced the error with log4j logs enabled.
>> Here the result (just reported the PduHandle with the problem, but if you 
need 
>> I have the complete logs):
>> 
>> 13/12/2006 14:30:30:131 DEBUG [pool-10-thread-22] [Log4jLogAdapter.debug] 
New 
>> pending request with handle PduHandle[1826954335]
>> ...
>> 13/12/2006 14:30:45:579 DEBUG [Timer-15] [Log4jLogAdapter.debug] Running 
>> pending request (3 left) with handle: PduHandle[1826954335]
>> ...
>> 13/12/2006 14:31:00:587 DEBUG [Timer-15] [Log4jLogAdapter.debug] Running 
>> pending request (2 left) with handle: PduHandle[1826954335]
>> ...
>> 13/12/2006 14:31:00:589 DEBUG [SNMPDriverDispatchPool.2] [Log4jLogAdapter.
>> debug] Looking up pending request with handle PduHandle[1826954335]
>> ...
>> 13/12/2006 14:31:00:591 ERROR [Timer-15] [Log4jLogAdapter.error] Failed to 
>> process pending request PduHandle[1826954335] because Task already 
scheduled or 
>> cancelled
>> java.lang.IllegalStateException: Task already scheduled or cancelled
>>         at java.util.Timer.sched(Timer.java:358)
>>         at java.util.Timer.schedule(Timer.java:170)
>>         at org.snmp4j.Snmp$PendingRequest.run(Snmp.java:1426)
>>         at java.util.TimerThread.mainLoop(Timer.java:512)
>>         at java.util.TimerThread.run(Timer.java:462)
>> ...
>> 13/12/2006 14:31:00:590 DEBUG [pool-10-thread-22] [Log4jLogAdapter.debug] 
>> Removed pending request with handle: PduHandle[1826954335]
>> ...
>> 
>> It seems there is a relation between the time the Timer-15 is checking the 
>> handle for the second time (14:31:00:587) and the time the answer comes (14:
31:
>> 00:589). They are really very closed one to the other.
>> Maybe a synchronization problem among threads?
>> 
>> Of course, after Timer-15 thread dies, no Snmp primitive to the agent is 
>> possible anymore and my application has to be restarted.
>> 
>> Can you help, please?
>> Regards,
>> Alberto
>> 
>> 
>> Frank wrote:
>> 
>>> Hi Fabian,
>>>
>>> We can catch only a RuntimeException and rethrow it. I have
>>> changed the code as follows for v1.7.1:
>>>
>>>      /**
>>>       * run
>>>       */
>>>      public synchronized void run() {
>>>        try {
>>>          if ((!finished) && (retryCount > 0)) {
>>> ...
>>>          }
>>>        }
>>>        catch (RuntimeException ex) {
>>>          logger.error("Failed to process pending request "+key+
>>>                       " because"+ex.getMessage(), ex);
>>>          throw ex;
>>>        }
>>>
>>> Best regards,
>>> Frank
>>>
>> 
>> 
>> --------------------
>> Alberto Mascheroni
>> Mob. +39-333-6314222
>> _______________________________________________
>> SNMP4J mailing list
>> SNMP4J at agentpp.org
>> http://lists.agentpp.org/mailman/listinfo/snmp4j
>
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>



--------------------
Alberto Mascheroni
Mob. +39-333-6314222