[SNMP4J] some SNMP4j issues...

[Frank Fock]

Renato,

This is not a problem of the exception handling inside
SNMP4J. There is no resource blocked or held inconsistently
by SNM4J when this runtime exception is thrown.

Best regards,
Frank

Renato Araújo Ferreira wrote:
> Frank,
> 
> I found that someone that configured the system to try to use the wrong 
> port (555555), but when I solved this error the timeout problem and the 
> ConcurrentModificationException stopped to ocurr. Is it an incorrect 
> exception handling of IllegalArgumentException inside the 
> DefaultUdpTransportMapping? Because an isolated error affect all SNMP 
> processing of snmp4j in VM.
> 
> Renato A. Ferreira
> 
> ----- Original Message ----- From: "Frank Fock" <fock at agentpp.com>
> To: "Renato Araújo Ferreira" <renato at flexvision.com.br>
> Cc: <snmp4j at agentpp.org>
> Sent: Wednesday, August 27, 2008 6:58 PM
> Subject: Re: [SNMP4J] some SNMP4j issues...
> 
> 
>> Hello Renato,
>>
>> Are you sure that each session is closed only once?
>> The last error you reported (ConcurrentMofificationException)
>> suggests that.
>>
>> The other errors/delays are caused by Java and
>> probably caused by heavy session (=UDP port)
>> creation and closing.
>> Changing the JRE (version) may help too.
>>
>> Best regards,
>> Frank
>>
>>
>> Renato Araújo Ferreira wrote:
>>> Hello all,
>>>
>>> I´m trying to use snmp4j in my application. It worked fine for single 
>>> threaded application, but I found some problems in a multithreaded 
>>> environment.
>>>
>>> Each thread has your own session initialized with:
>>>
>>>    TransportMapping transporteUDP = new DefaultUdpTransportMapping();
>>>    this.sessaoSNMP = new Snmp(transporteUDP);
>>>    this.sessaoSNMP.listen();
>>>
>>> And closed with:
>>>
>>>    this.sessaoSNMP.close();
>>>
>>> These sessions are reused in all thread's life cycle only changing 
>>> their CommunityTarget and UserTarget. But, at end of process, one 
>>> last target (randomly, not the same) always wait too many time, 
>>> between 250 and 300 seconds, in method org.snmp4j.Snmp.get with this 
>>> stack:
>>>
>>>    "DefaultUDPTransportMapping_1.1.0.160/0" daemon prio=1 
>>> tid=0x086b8070 nid=0x7c51 runnable [0x8b948000..0x8b948ec0]
>>>            at java.net.PlainDatagramSocketImpl.receive0(Native Method)
>>>            at 
>>> java.net.PlainDatagramSocketImpl.receive(PlainDatagramSocketImpl.java:136) 
>>>
>>>            - locked <0x926b9918> (a java.net.PlainDatagramSocketImpl)
>>>            at java.net.DatagramSocket.receive(DatagramSocket.java:712)
>>>            - locked <0xb1b6d400> (a java.net.DatagramPacket)
>>>            - locked <0x926bacd0> (a java.net.DatagramSocket)
>>>            at 
>>> org.snmp4j.transport.DefaultUdpTransportMapping$ListenThread.run(Unknown 
>>> Source)
>>>            at java.lang.Thread.run(Thread.java:595)
>>>            at 
>>> org.snmp4j.util.DefaultThreadFactory$WorkerThread.run(Unknown Source)
>>>
>>>    "Coletando: public at 00-18-F3-C7-71-05" daemon prio=1 tid=0x086244d8 
>>> nid=0x7c38 in Object.wait() [0x8c76a000..0x8c76ae40]
>>>            at java.lang.Object.wait(Native Method)
>>>            - waiting on <0x92ae9730> (a 
>>> org.snmp4j.Snmp$SyncResponseListener)
>>>            at java.lang.Object.wait(Object.java:474)
>>>            at org.snmp4j.Snmp.send(Unknown Source)
>>>            - locked <0x92ae9730> (a 
>>> org.snmp4j.Snmp$SyncResponseListener)
>>>            at org.snmp4j.Snmp.send(Unknown Source)
>>>            at org.snmp4j.Snmp.get(Unknown Source)
>>>            ...
>>>
>>> Sometimes I'm getting a "IllegalArgumentException: port out of 
>>> range:555555" error with this stack:
>>>
>>>    java.lang.IllegalArgumentException: port out of range:555555
>>>            at 
>>> java.net.InetSocketAddress.<init>(InetSocketAddress.java:83)
>>>            at 
>>> org.snmp4j.transport.DefaultUdpTransportMapping.sendMessage(Unknown 
>>> Source)
>>>            at org.snmp4j.MessageDispatcherImpl.sendMessage(Unknown 
>>> Source)
>>>            at org.snmp4j.MessageDispatcherImpl.sendPdu(Unknown Source)
>>>            at org.snmp4j.Snmp.sendMessage(Unknown Source)
>>>            at org.snmp4j.Snmp$PendingRequest.run(Unknown Source)
>>>            at java.util.TimerThread.mainLoop(Timer.java:512)
>>>            at java.util.TimerThread.run(Timer.java:462)
>>>
>>> And, finally, sometimes I'm getting a 
>>> "ConcurrentModificationException" error using a iterator (method 
>>> Iterator.next()) at end of process, when all the SNMP communications 
>>> are already finished. This code was already there before I'm using 
>>> SNMP4j and, as I found some information about bugs like this in the 
>>> web, I think so that could be something with my implementation of 
>>> SNMP4j.
>>>
>>> OMG, a large email, but could someone help me??
>>>
>>> Thankss....
>>>
>>> Renato A. Ferreira
>>> _______________________________________________
>>> SNMP4J mailing list
>>> SNMP4J at agentpp.org
>>> http://lists.agentpp.org/mailman/listinfo/snmp4j
>>
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