How to enable Apache graceful restart in Plesk?
By default, Plesk does not use Apache graceful restart for applying new settings. As a result Apache will be restarted every time you change hosting settings through the Plesk GUI. This can lead to unwanted interruptions of sites operation.
To enable graceful restart, add "restart_apache_gracefully" with a "true" value to the "misc" table of the "psa" database:
Log in to the Plesk database:
MYSQL_PWD=`cat /etc/psa/.psa.shadow` mysql -u admin psa
Apply the following SQL query:
mysql> INSERT INTO misc VALUES ('restart_apache_gracefully', 'true');