service apache2 restart
or
apachectl -k restart
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===== Restart Gracefully =====
Ifrestarting the web server on a live website, it should be done gracefully.
A graceful restart tells the web sever to finish any active connections before restarting.
* This means that active visitors to the site will be able to finish downloading anything already in progress before the server restarts.
sudo /etc/init.d/apache2 graceful
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