[logback-user] What would cause "java.lang.NoClassDefFoundError: ch/qos/logback/classic/spi/ThrowableProxy" in long running daemon

[Adam Gent]

Are you redeploying over old jars and not shutting down your existing
process and/or relying on hot deploy?
Are you absolutely sure your apps jars are not changing while the
process is running? Check timestamp. Check MD5 sums.
Why you see ThrowableProxy coming up as an error probably has nothing
to do with logback. I bet there was a previous NoClassDef errors that
should have be thrown and the output should of been shown but when
that error was logged your application had not yet logged any
exceptions yet and thus loaded the ThrowableProxy class which was also
missing/corrupt.

-Adam

On Mon, Aug 31, 2015 at 12:23 PM, Scott Plante <splante at insightsys.com> wrote:
> If literally everything is an NFS drive, you could edit your app startup script to create a RAM disk, copy the jar files, and use those instead.
>
> http://www.jamescoyle.net/how-to/943-create-a-ram-disk-in-linux
>
> Scott
>
> ----- Original Message -----
>
> From: "Fred Toth" <ftoth at synernet.com>
> To: "logback users list" <logback-user at qos.ch>
> Sent: Monday, August 31, 2015 11:03:31 AM
> Subject: Re: [logback-user] What would cause "java.lang.NoClassDefFoundError: ch/qos/logback/classic/spi/ThrowableProxy" in long running daemon
>
> Hi David,
>
> For better or worse, these particular apps are on one of these modern
> disk systems where EVERYTHING is an NFS mount. Supposed to "just work",
> you know.
>
> Thanks,
> Fred
>
> On 8/31/15 6:55 AM, David Roussel wrote:
>> Are you storing your jar files on the NFS mounts?
>>
>> Seem like a bad idea if you are. If a network error causes an exception, and the exception handler calls a class that has not been loaded yet, the class loader will try to load it.
>>
>> The network is unreliable, you must be able to handle network failures.
>>
>> If you are using NFS for ease of deployment, say for batch jobs, there is another way.
>>
>> David
>>
>>> On 30 Aug 2015, at 01:58, Fred Toth <ftoth at synernet.com> wrote:
>>>
>>> Hi,
>>>
>>> We have multiple production processes that run 24 hours a day, 7 days a week. All use slf4j/logback and recently we had several of these (seemingly coincidentally) spew:
>>>
>>> java.lang.NoClassDefFoundError: ch/qos/logback/classic/spi/ThrowableProxy
>>>
>>> These are long running processes where nothing has changed recently. Obviously the logback jars are available, in the right place, etc.
>>>
>>> I'm stumped. There are some hints of some possible system related problem (like missing NFS mount, possibly).
>>>
>>> Does logback dynamically load the above class? Again, this error is out of the blue, from a process that may have been running for days or weeks.
>>>
>>> Any ideas?
>>>
>>> We're using version logback 1.0.13.
>>>
>>> If I google the above, there are some references to "Spring Boot" which we are not using. However, we are using Spring Integration, in case that matters.
>>>
>>> Any ideas?
>>>
>>> Thanks,
>>> Fred
>>>
>>> _______________________________________________
>>> Logback-user mailing list
>>> Logback-user at qos.ch
>>> http://mailman.qos.ch/mailman/listinfo/logback-user
>> _______________________________________________
>> Logback-user mailing list
>> Logback-user at qos.ch
>> http://mailman.qos.ch/mailman/listinfo/logback-user
>>
>
> _______________________________________________
> Logback-user mailing list
> Logback-user at qos.ch
> http://mailman.qos.ch/mailman/listinfo/logback-user
> _______________________________________________
> Logback-user mailing list
> Logback-user at qos.ch
> http://mailman.qos.ch/mailman/listinfo/logback-user



-- 
CTO
SnapHop (snaphop.com)
(twitter) @agentgt (linkedin) http://www.linkedin.com/in/agentgt
(cell) 781-883-5182