[SNMP4J] some SNMP4j issues...

[Renato Araújo Ferreira]

Gene,

Multiple thread access many targets with SNMP4J, but only one target has a 
wrong snmp port configured as 555555. Now I configured our database to 
accept only values between 0~65535 to avoid this problem, but I'm worried 
yet about any other system or communication error that could happen and 
bring back these erros.

The ConcurrentModificationException and the bad timeout behaviour happen 
when the IllegalArgumentException is thrown to only one target and only one 
thread. And the ConcurrentModificationException, for example, happen at 
final of process on thread "main", when all threads and instantes of snmp 
were already closed. When I see the message 'Exception in thread "Timer-0" 
java.lang.IllegalArgumentException: port out of range:555555', I think that 
the "Timer-0" thread is dead without finish their job, what could leak some 
resources.

Is there something that I can do to do a diagnose of this problema to prove 
if It's happening or not? A specific profiler or debugger that runs under 
linux console mode?

Renato A. Ferreira

----- Original Message ----- 
From: "Eugene R. Snider" <gene at cvtt.net>
To: "Renato Araújo Ferreira" <renato at flexvision.com.br>
Cc: <snmp4j at agentpp.org>
Sent: Wednesday, September 03, 2008 12:39 AM
Subject: Re: [SNMP4J] some SNMP4j issues...


> Renato,
>
> No, the concurrent modification exception is probably what happens when 
> multiple threads attempt to use the wrong port (555555). If one thread is 
> in the middle of exception processing for the illegal argument any other 
> threads will get the ConcurrentModificationException, if enough threads 
> gets started they will also generate timeouts.
>
> It's not an isolated error, it's a continuous cycle of sends in multiple 
> threads.
>
> Also I agree with Frank that you should upgrade your Java version.
>
> Gene
>
>
> 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.
>>