Re: [Wrapper-user] How to properly handle WRAPPER_CTRL_TERM_EVENT?

[David H. <dho...@gm...>]

Leif,

I'm about ready to deploy this change.  I understand it needs to be stopped
but since this is 'installed' as a daemon do I have to 'undo' that first?
Or just stop and restart?

Thanks,
-Dave

On Tue, May 17, 2011 at 1:09 PM, Leif Mortenson <
lei...@ta...> wrote:

> David,
> The controlEvent method gives you a chance to either handle or ignore
> the signal within the JVM process.  This is a very old API and the
> problem with it is that the Wrapper process may also receive a TERM
> signal.  If that happens, the Wrapper will proceed to initiate the
> shutdown process regardless of what this method does.   For this
> reason, this method is more useful as a reporting method.
>
> To prevent your application from responding to TERM signals, you will
> want to use the wrapper.ignore_signals property
> http://wrapper.tanukisoftware.com/doc/english/prop-ignore-signals.html
>
> On UNIX, the recommended way of doing this is to set the
> IGNORE_SIGNALS variable at the top of the shell script that comes with
> the Wrapper.  Make sure the Wrapper is stopped when this change is
> made as it changes the way the script controls the Wrapper.
> Please see the above page for more details.
>
> Let me know how this works for you.
>
> Cheers,
> Leif
>
> On Tue, May 17, 2011 at 5:16 PM, David Hoffer <dho...@gm...> wrote:
> > I have the wrapper installed on Linux as a service and need as close
> > to 100% up time as is possible.  The wrapper recently received a
> > WRAPPER_CTRL_TERM_EVENT and shut the app and wrapper down.  My
> > controlEvent() is like this...as copied from some JSW sample code...
> >
> > public void controlEvent(int event) {
> >
> >         try {
> >             if (WrapperManager.isControlledByNativeWrapper()) {
> >                 // The Wrapper will take care of this event
> >             } else {
> >                 // We are not being controlled by the Wrapper, so
> > handle the event ourselves.
> >                 if ((event == WrapperManager.WRAPPER_CTRL_C_EVENT) ||
> > (event == WrapperManager.WRAPPER_CTRL_CLOSE_EVENT) || (event ==
> > WrapperManager.WRAPPER_CTRL_SHUTDOWN_EVENT)) {
> >                     log.warn("We are handling the received event
> > ourselves and we are stopping the service");
> >                     WrapperManager.stop(0);
> >                 }
> >             }
> >         }
> >     }
> >
> > Now I see that recent javadocs say to use...(unless one knows what
> > they are doing)
> >
> > public void controlEvent( int event )
> >  {
> >       if ( ( event == WrapperManager.WRAPPER_CTRL_LOGOFF_EVENT )  &&
> > WrapperManager.isLaunchedAsService() )
> >        {
> >            // Ignore
> >        }  else   {
> >           WrapperManager.stop( 0 );
> >        }
> >  }
> >
> > It seems neither of these handle WRAPPER_CTRL_TERM_EVENT in a way that
> > provides 100% up time, rather it just shuts things down cleanly.
> >
> > What is the right way to handle this?  I.e. should I ignore the
> > signal?  should I restart after shutdown?  How?
> >
> > Thanks,
> > -Dave
>
>
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