1. start
2. restart
3. graceful
4. stop
5. graceful-stop

A note about graceful Apache webserver restart

You need to send USR1 signal to the apache server:

This (USR1) signal causes the parent process to advise the children to exit after their current request (or to exit immediately if they’re not serving anything). The parent re-reads its configuration files and re-opens its log files. As each child dies off the parent replaces it with a child from the new generation of the configuration, which begins serving new requests immediately.

Command syntax to gracefully restart the Apache 1.x/2.x after changing config file

Type the following command as a root user:

apachectl -k graceful

OR

apache2ctl -k graceful

You can also use Linux distro specific Sys V init script as follows to gracefully reload the server. The following example works on RHEL/CentOS Linux and friends only:

/etc/init.d/httpd graceful

OR

/sbin/service httpd graceful

Debian / Ubuntu Linux and friends use the following syntax:

/etc/init.d/apache2 reload

Monitoring apache progress

After you have signaled Apache 2, you can read apache error_log file about its progress by issuing the following tail command:

## For RHEL / CentOS and friends ##
tail -f /var/log/httpd/error_log
 
## For  Debian / Ubuntu and friends ##
tail -f /var/log/apache2/error.log
 
## FreeBSD Unix ##
tail -f /var/log/httpd-error.log