Dear,
i have apache2 on debian box i have bugzilla appication on this apache2 which is perl application.

when i try to access it from my browser it was working well but after some time i found that the apache 2 shutdown and i see it's log at /var/logs/apache2/error.log i get this message

[Tue Sep 06 10:36:12 2005] [notice] Graceful restart requested, doing restart
[Tue Sep 06 10:36:12 2005] [notice] Apache/2.0.54 (Debian GNU/Linux) PHP/4.3.10-15 mod_perl/1.999.21 Perl/v5.8.4 configured -- resuming normal operations

what is the solution to fix this problem.

I'm not sure I see any errors.

Do you mean it is shutting down by itself?

yes it shutdown by it selft and restart after 20 second as i read on web.
all applications that has a session the session end when apache stop and start so all login clients logout.

If you got any updates then its possible your apache needed restarting by the package manager. It has shut down and restarted rather than crashing, is that correct?

Some logrotation scripts also force this to happen.